From nek5000-users at lists.mcs.anl.gov Fri Jan 3 19:40:03 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Sat, 4 Jan 2014 01:40:03 +0000 Subject: [Nek5000-users] turbulent 3d box In-Reply-To: References: , , , , , , Message-ID: Barak, I suggest comparing the SIZE files for various examples. From there you should be able to see how to properly modify SIZE to change the resolution. Of course, you'll need to reduce dt to maintain CFL ~ 0.5 Paul ________________________________________ From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] Sent: Sunday, December 22, 2013 4:25 PM To: nek5000-users at lists.mcs.anl.gov Subject: Re: [Nek5000-users] turbulent 3d box It didn't work (I tried both options). Do you have working example? (see my previous email and my attachment). Barak On 12/22/2013 11:20 PM, nek5000-users at lists.mcs.anl.gov wrote: > > Hi Paul, > On 12/22/2013 11:14 PM, nek5000-users at lists.mcs.anl.gov wrote: >> >> Hi Barak, >> >> You can either increase lx1,ly1, lz1 in SIZE and re-make, or you >> can change nelx,nely,nelz in the .box file. >> > Thanks. >> Did you resolve the issue with the initial condition? >> > See my previous email. I have inside further questions. > Best regards, > Barak > > >> Paul >> ________________________________________ >> From: nek5000-users-bounces at lists.mcs.anl.gov >> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >> Sent: Sunday, December 22, 2013 3:05 PM >> To: nek5000-users at lists.mcs.anl.gov >> Subject: Re: [Nek5000-users] turbulent 3d box >> >> Hi Paul, >> Before I run problems with smaller viscosity: how I increase the >> resolution? and remesh the box? >> Barak >> >> On 12/22/2013 10:24 PM, nek5000-users at lists.mcs.anl.gov wrote: >>> >>> Hi Barak, >>> >>> When I compute the L2 norm of the function, given as: >>> >>> v2 = [ sum_i vx_i b_i vx_i + vy_i b_i vy_i + vz_i b_i vz_i >>> / sum_i b_i ]^(1/2) >>> >>> it comes out to ~ 2.23 >>> >>> Note that there are some places where ux==2, uy==0, uz==1, >>> which would give an L2 norm of >>> >>> sqrt (2*2 + 0*0 + 1*1) = sqrt(5) > sqrt(3) >>> >>> ? >>> >>> Paul >>> >>> ________________________________________ >>> From: nek5000-users-bounces at lists.mcs.anl.gov >>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>> Sent: Sunday, December 22, 2013 11:04 AM >>> To: nek5000-users at lists.mcs.anl.gov >>> Subject: Re: [Nek5000-users] turbulent 3d box >>> >>> Hi Paul, >>> My definition for velocity magnitude is: >>> |v|=sqrt(ux^2+uy^2+uz^2) >>> so if you see, there are two components in the form: >>> cos^2(x)+sin^2(x) >>> etc in each direction >>> so in fact >>> |v|=sqrt(3) for any x,y,z. >>> Isn't correct? >>> Barak >>> >>> On 12/22/2013 05:05 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>> Hi Barak, >>>> >>>> If your initial condition is: >>>> >>>> ux=(cos(y)+sin(z)) >>>> uy=(cos(z)+sin(x)) >>>> uz=(cos(x)+sin(y)) >>>> >>>> and your domain is [0,2pi]^3, how is it possible that your velocity >>>> magnitude >>>> is less than 2? >>>> >>>> >>>> What is your measure of velocity magnitude? When I compute the L2 >>>> norm of this initial condition I'm seeing about 2.3+ >>>> >>>> Paul >>>> >>>> ------------------------------------------------------------------------ >>>> >>>> *From:* nek5000-users-bounces at lists.mcs.anl.gov >>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>> *Sent:* Sunday, December 22, 2013 7:53 AM >>>> *To:* nek5000-users at lists.mcs.anl.gov >>>> *Subject:* Re: [Nek5000-users] turbulent 3d box >>>> >>>> Hi Paul, >>>> It seems that something does not work, comparing my simulations using a >>>> standard spectral code (pseudo-spectral). For nu=0.1, I used 16 points >>>> for each space direction. Now for this case, the nonlinear terms vanish >>>> (just cancel each other) and the solution is just the ABC flow if you >>>> set it as initial condition. Then since the forcing is f=nu*ABC the >>>> dissipation term (Laplacian) dissipation=-nu*ABC and therefore the >>>> initial value (ABC) remains as it is. If we decrease the viscosity >>>> above >>>> the critical value of 1/12 (if I remember correctly) there is a >>>> bifurcation (Hopf...) and we obtain a new periodic solution (in time), >>>> where the ABC modes are dominating combined with some high wave numbers >>>> that are oscillating. >>>> >>>> >From my first tests using NEK, I find that the velocity field (for >>>> nu>1/12) does not agree with the above characteristics. For example, >>>> the >>>> max magnitude of the velocity field should be for the ABC flow sqrt(3), >>>> whereas here I get a value close to 2.5. >>>> >>>> Do you have any idea what's wrong? >>>> If you wish to read some literature about the ABC flow as a forcing for >>>> Navier Stokes or as a prescribed velocity for generation of magnetic >>>> field (i.e., kinematic generation of magnetic field MHD): >>>> >>>> 1. D. Galloway and U. Frisch. A numerical investigation of magnetic >>>> field generation in a flow with chaotic streamlines. Geophysical & >>>> Astrophysical Fluid Dynamics, 29(1):13?18, 1984. >>>> >>>> 2. D. Galloway and U. Frisch. Dynamo action in a family of flows with >>>> chaotic streamlines. >>>> Geophysical & Astrophysical Fluid Dynamics, 36(1):53?83, 1986. >>>> >>>> 3. Podvigina, Pouquet, On the non-linear stability of the 1:1:1 ABC >>>> flow, >>>> Phys. D, Vol. 75, 4, 1994. >>>> >>>> >>>> With my best wishes, >>>> Barak >>>> >>>> >>>> Quoting nek5000-users at lists.mcs.anl.gov >>>> : >>>> >>>>> Hi Barak, >>>>> >>>>> Thanks for the note about the ABC flow -- that's very useful. >>>>> >>>>> What is your target viscosity? >>>>> If you want it to be 0.1, then you would set param 2 in the .rea file >>>>> to be 0.1. >>>>> Setting param 2 = -0.1 would imply that Re=0.1 or equivalently nu=10. >>>>> Does this resolve the issue for you? >>>>> >>>>> Once it's working we could add it as a documented example in the >>>>> example >>>>> suite. >>>>> >>>>> Thanks! >>>>> >>>>> Paul >>>>> ________________________________________ >>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>> >>>>> [nek5000-users-bounces at lists.mcs.anl.gov >>>>> ] on behalf of >>>>> nek5000-users at lists.mcs.anl.gov >>>>> >>>>> [nek5000-users at lists.mcs.anl.gov >>>>> ] >>>>> Sent: Saturday, December 21, 2013 5:24 PM >>>>> To: nek5000-users at lists.mcs.anl.gov >>>>> >>>>> Subject: Re: [Nek5000-users] turbulent 3d box >>>>> >>>>> Hi Paul, >>>>> Regarding the 3dbox: >>>>> The forcing which I propose is known as the ABC flow >>>>> (Arnold-Beltrami-Childress) and has steady solutions (in the form >>>>> of ABC >>>>> flow) with Re=1/nu (nu the viscosity) Re=<12 (in periodic box). >>>>> The forcing should be in the form: >>>>> f=Re*ABC in order to balance the dissipation term. >>>>> This settings can serve as a benchmark for pure hydro/mhd problems. >>>>> >>>>> I tried to fix the example which you have sent me, but I don't succeed >>>>> retreiving the expected values. >>>>> I attach the relevant files( tarball file). >>>>> Best regards, >>>>> Barak >>>>> >>>>> >>>>> >>>>> On 12/18/2013 03:29 AM, nek5000-users at lists.mcs.anl.gov >>>>> wrote: >>>>> >>>>>> Hi Barak, >>>>>> >>>>>> I added a 3d periodic box under "3dbox" in the examples >>>>>> directory. >>>>>> >>>>>> Paul >>>>>> >>>>>> >>>>>> Dear nek's, >>>>>> I would like to run the following problem: >>>>>> a 3D periodic box, small viscosity and the following forcing: >>>>>> >>>>>> fx=cos(y)+sin(z) >>>>>> fy=cos(z)+sin(x) >>>>>> fz=cos(x)+sin(y) >>>>>> >>>>>> Do you have a similar example? >>>>>> >>>>>> Many thanks, >>>>>> Barak >>>>>> >>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl >>>>> .govhttps://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>>> >>>> >>>> >>>> >>>> >>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > _______________________________________________ Nek5000-users mailing list Nek5000-users at lists.mcs.anl.gov https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users From nek5000-users at lists.mcs.anl.gov Sat Jan 4 12:02:14 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Sat, 4 Jan 2014 13:02:14 -0500 Subject: [Nek5000-users] fft in nek5000 or Visit ? Message-ID: Dear Neks I have my turbulent flow in a 3D box for which I would like to perform a Fourier analysis in one direction (y) at several selected time steps in order to find the discretized spectral representation (up to resolution of say N=128 wave numbers) of streamwise vorticity (w_x). I have been trying to find the best way to approach this in nek by reading the user mailing list but am troubled to decide and would appreciate it if the experienced users could guide me: 1) Using int_tp tool (in repo, trunk/tool/) one can interpolate the nek SEM output results to uniform, SEM and non-uniform (selected points) but I guess this only works for small grids? At least I got seg fault for my larger grids. Alternatively, we can use "ifreguo = .true." in userchk via post-processing the data in parallel. And then use a separate fft library (eg. MATLAB) to read in the uniform grid and do fft. But there will be memory issues for larger datasets. How can I resolve this? 2) I noticed that Visit has an FFT operator (at least in my v 2.6.3) for which I could not find any documentation. Does anyone have any knowledge of how it works? 3) One could also do the fft by adding proper subroutines in .usr file and calling them in userchk. Does anyone here have the right set of subroutines for this purpose? Thank you, Hesam -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Thu Jan 9 10:26:43 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Thu, 09 Jan 2014 17:26:43 +0100 Subject: [Nek5000-users] The first time step in a Nek file must contain a mesh error Message-ID: Hello, I am using VisIT for nek5000, I tried some of the tutorials from Nek5000. I was able to launch and create the metadata file for Eddy_uv example. I tried to do the same for the Helix Pipe example but when I loaded the metadata file into VisIT, I got an error saying " The first time step in a Nek file must contain a mesh " This is my metadata file for the pipe helix example --------------------------------------------------------------------- NEK5000 version: 1.0 helix.rea filetemplate: helix0.f%05d firsttimestep: 1 numtimesteps: 1 --------------------------------------------------------------------- Can some one tell me how to add mesh to the first time step. Thank you, Kamal From nek5000-users at lists.mcs.anl.gov Thu Jan 9 16:31:29 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Thu, 9 Jan 2014 16:31:29 -0600 Subject: [Nek5000-users] The first time step in a Nek file must contain a mesh error In-Reply-To: References: Message-ID: Hi Kamal, It looks like your metadata file for Visit needs to be changed to: filetemplate: helix%01d.f%05d This should result in the example working as expected. You can check that the helix0.f000001 file has the mesh by: head -1 helix0.f00001 |strings There should be an 'X' in the alpha-character line that signifies the xyz data is found in that file. On Thu, Jan 9, 2014 at 10:26 AM, wrote: > Hello, > > I am using VisIT for nek5000, I tried some of the tutorials from Nek5000. > > I was able to launch and create the metadata file for Eddy_uv example. > > I tried to do the same for the Helix Pipe example but when I loaded the > metadata file into VisIT, I got an error saying " The first time step in a > Nek file must contain a mesh " > > This is my metadata file for the pipe helix example > --------------------------------------------------------------------- > NEK5000 > version: 1.0 > helix.rea > filetemplate: helix0.f%05d > firsttimestep: 1 > numtimesteps: 1 > --------------------------------------------------------------------- > > Can some one tell me how to add mesh to the first time step. > > > Thank you, > > Kamal > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Fri Jan 10 04:00:43 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Fri, 10 Jan 2014 11:00:43 +0100 Subject: [Nek5000-users] The first time step in a Nek file must contain a mesh error In-Reply-To: References: Message-ID: Hi Thanks a lot for the reply and it worked. I have couple of more questions 1) How can I create a .rea for a specific geometry say ' A sudden expansion pipe ' or a ' Diverging pipe ' 2) What tool I should use to create that mesh. Thank you On 09/01/2014 23:31, nek5000-users at lists.mcs.anl.gov wrote: > Hi Kamal, > > It looks like your metadata file for Visit needs to be changed to: > > filetemplate: helix%01d.f%05d > > > This should result in the example working as expected. You can check > that the helix0.f000001 file has the mesh by: > head -1 helix0.f00001 |strings > There should be an 'X' in the alpha-character line that signifies the > xyz data is found in that file. > > > On Thu, Jan 9, 2014 at 10:26 AM, > wrote: > > Hello, > > I am using VisIT for nek5000, I tried some of the tutorials from > Nek5000. > > I was able to launch and create the metadata file for Eddy_uv example. > > I tried to do the same for the Helix Pipe example but when I > loaded the metadata file into VisIT, I got an error saying " The > first time step in a Nek file must contain a mesh " > > This is my metadata file for the pipe helix example > --------------------------------------------------------------------- > NEK5000 > version: 1.0 > helix.rea > filetemplate: helix0.f%05d > firsttimestep: 1 > numtimesteps: 1 > --------------------------------------------------------------------- > > Can some one tell me how to add mesh to the first time step. > > > Thank you, > > Kamal > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > > > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Fri Jan 10 08:30:44 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Fri, 10 Jan 2014 16:30:44 +0200 Subject: [Nek5000-users] turbulent 3d box In-Reply-To: References: , , , , , , Message-ID: Hi Paul, Thanks for your help till now. Regarding the proper discretization of the 3d turbulent box setup. When simulating using a standard spectral method the smallest scale defines the highest wavenumber kmax. What is its equivalent in SEM? Happy new year 2014, Barak On 01/04/2014 03:40 AM, nek5000-users at lists.mcs.anl.gov wrote: > > Barak, > > I suggest comparing the SIZE files for various examples. From there you should > be able to see how to properly modify SIZE to change the resolution. > > Of course, you'll need to reduce dt to maintain CFL ~ 0.5 > > Paul > > ________________________________________ > From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] > Sent: Sunday, December 22, 2013 4:25 PM > To: nek5000-users at lists.mcs.anl.gov > Subject: Re: [Nek5000-users] turbulent 3d box > > It didn't work (I tried both options). Do you have working example? > (see my previous email and my attachment). > Barak > > On 12/22/2013 11:20 PM, nek5000-users at lists.mcs.anl.gov wrote: >> >> Hi Paul, >> On 12/22/2013 11:14 PM, nek5000-users at lists.mcs.anl.gov wrote: >>> >>> Hi Barak, >>> >>> You can either increase lx1,ly1, lz1 in SIZE and re-make, or you >>> can change nelx,nely,nelz in the .box file. >>> >> Thanks. >>> Did you resolve the issue with the initial condition? >>> >> See my previous email. I have inside further questions. >> Best regards, >> Barak >> >> >>> Paul >>> ________________________________________ >>> From: nek5000-users-bounces at lists.mcs.anl.gov >>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>> Sent: Sunday, December 22, 2013 3:05 PM >>> To: nek5000-users at lists.mcs.anl.gov >>> Subject: Re: [Nek5000-users] turbulent 3d box >>> >>> Hi Paul, >>> Before I run problems with smaller viscosity: how I increase the >>> resolution? and remesh the box? >>> Barak >>> >>> On 12/22/2013 10:24 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>> Hi Barak, >>>> >>>> When I compute the L2 norm of the function, given as: >>>> >>>> v2 = [ sum_i vx_i b_i vx_i + vy_i b_i vy_i + vz_i b_i vz_i >>>> / sum_i b_i ]^(1/2) >>>> >>>> it comes out to ~ 2.23 >>>> >>>> Note that there are some places where ux==2, uy==0, uz==1, >>>> which would give an L2 norm of >>>> >>>> sqrt (2*2 + 0*0 + 1*1) = sqrt(5) > sqrt(3) >>>> >>>> ? >>>> >>>> Paul >>>> >>>> ________________________________________ >>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>> Sent: Sunday, December 22, 2013 11:04 AM >>>> To: nek5000-users at lists.mcs.anl.gov >>>> Subject: Re: [Nek5000-users] turbulent 3d box >>>> >>>> Hi Paul, >>>> My definition for velocity magnitude is: >>>> |v|=sqrt(ux^2+uy^2+uz^2) >>>> so if you see, there are two components in the form: >>>> cos^2(x)+sin^2(x) >>>> etc in each direction >>>> so in fact >>>> |v|=sqrt(3) for any x,y,z. >>>> Isn't correct? >>>> Barak >>>> >>>> On 12/22/2013 05:05 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>> Hi Barak, >>>>> >>>>> If your initial condition is: >>>>> >>>>> ux=(cos(y)+sin(z)) >>>>> uy=(cos(z)+sin(x)) >>>>> uz=(cos(x)+sin(y)) >>>>> >>>>> and your domain is [0,2pi]^3, how is it possible that your velocity >>>>> magnitude >>>>> is less than 2? >>>>> >>>>> >>>>> What is your measure of velocity magnitude? When I compute the L2 >>>>> norm of this initial condition I'm seeing about 2.3+ >>>>> >>>>> Paul >>>>> >>>>> ------------------------------------------------------------------------ >>>>> >>>>> *From:* nek5000-users-bounces at lists.mcs.anl.gov >>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>> *Sent:* Sunday, December 22, 2013 7:53 AM >>>>> *To:* nek5000-users at lists.mcs.anl.gov >>>>> *Subject:* Re: [Nek5000-users] turbulent 3d box >>>>> >>>>> Hi Paul, >>>>> It seems that something does not work, comparing my simulations using a >>>>> standard spectral code (pseudo-spectral). For nu=0.1, I used 16 points >>>>> for each space direction. Now for this case, the nonlinear terms vanish >>>>> (just cancel each other) and the solution is just the ABC flow if you >>>>> set it as initial condition. Then since the forcing is f=nu*ABC the >>>>> dissipation term (Laplacian) dissipation=-nu*ABC and therefore the >>>>> initial value (ABC) remains as it is. If we decrease the viscosity >>>>> above >>>>> the critical value of 1/12 (if I remember correctly) there is a >>>>> bifurcation (Hopf...) and we obtain a new periodic solution (in time), >>>>> where the ABC modes are dominating combined with some high wave numbers >>>>> that are oscillating. >>>>> >>>>> >From my first tests using NEK, I find that the velocity field (for >>>>> nu>1/12) does not agree with the above characteristics. For example, >>>>> the >>>>> max magnitude of the velocity field should be for the ABC flow sqrt(3), >>>>> whereas here I get a value close to 2.5. >>>>> >>>>> Do you have any idea what's wrong? >>>>> If you wish to read some literature about the ABC flow as a forcing for >>>>> Navier Stokes or as a prescribed velocity for generation of magnetic >>>>> field (i.e., kinematic generation of magnetic field MHD): >>>>> >>>>> 1. D. Galloway and U. Frisch. A numerical investigation of magnetic >>>>> field generation in a flow with chaotic streamlines. Geophysical & >>>>> Astrophysical Fluid Dynamics, 29(1):13?18, 1984. >>>>> >>>>> 2. D. Galloway and U. Frisch. Dynamo action in a family of flows with >>>>> chaotic streamlines. >>>>> Geophysical & Astrophysical Fluid Dynamics, 36(1):53?83, 1986. >>>>> >>>>> 3. Podvigina, Pouquet, On the non-linear stability of the 1:1:1 ABC >>>>> flow, >>>>> Phys. D, Vol. 75, 4, 1994. >>>>> >>>>> >>>>> With my best wishes, >>>>> Barak >>>>> >>>>> >>>>> Quoting nek5000-users at lists.mcs.anl.gov >>>>> : >>>>> >>>>>> Hi Barak, >>>>>> >>>>>> Thanks for the note about the ABC flow -- that's very useful. >>>>>> >>>>>> What is your target viscosity? >>>>>> If you want it to be 0.1, then you would set param 2 in the .rea file >>>>>> to be 0.1. >>>>>> Setting param 2 = -0.1 would imply that Re=0.1 or equivalently nu=10. >>>>>> Does this resolve the issue for you? >>>>>> >>>>>> Once it's working we could add it as a documented example in the >>>>>> example >>>>>> suite. >>>>>> >>>>>> Thanks! >>>>>> >>>>>> Paul >>>>>> ________________________________________ >>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>> >>>>>> [nek5000-users-bounces at lists.mcs.anl.gov >>>>>> ] on behalf of >>>>>> nek5000-users at lists.mcs.anl.gov >>>>>> >>>>>> [nek5000-users at lists.mcs.anl.gov >>>>>> ] >>>>>> Sent: Saturday, December 21, 2013 5:24 PM >>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>> >>>>>> Subject: Re: [Nek5000-users] turbulent 3d box >>>>>> >>>>>> Hi Paul, >>>>>> Regarding the 3dbox: >>>>>> The forcing which I propose is known as the ABC flow >>>>>> (Arnold-Beltrami-Childress) and has steady solutions (in the form >>>>>> of ABC >>>>>> flow) with Re=1/nu (nu the viscosity) Re=<12 (in periodic box). >>>>>> The forcing should be in the form: >>>>>> f=Re*ABC in order to balance the dissipation term. >>>>>> This settings can serve as a benchmark for pure hydro/mhd problems. >>>>>> >>>>>> I tried to fix the example which you have sent me, but I don't succeed >>>>>> retreiving the expected values. >>>>>> I attach the relevant files( tarball file). >>>>>> Best regards, >>>>>> Barak >>>>>> >>>>>> >>>>>> >>>>>> On 12/18/2013 03:29 AM, nek5000-users at lists.mcs.anl.gov >>>>>> wrote: >>>>>> >>>>>>> Hi Barak, >>>>>>> >>>>>>> I added a 3d periodic box under "3dbox" in the examples >>>>>>> directory. >>>>>>> >>>>>>> Paul >>>>>>> >>>>>>> >>>>>>> Dear nek's, >>>>>>> I would like to run the following problem: >>>>>>> a 3D periodic box, small viscosity and the following forcing: >>>>>>> >>>>>>> fx=cos(y)+sin(z) >>>>>>> fy=cos(z)+sin(x) >>>>>>> fz=cos(x)+sin(y) >>>>>>> >>>>>>> Do you have a similar example? >>>>>>> >>>>>>> Many thanks, >>>>>>> Barak >>>>>>> >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl >>>>>> .govhttps://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > From nek5000-users at lists.mcs.anl.gov Fri Jan 10 09:07:55 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Fri, 10 Jan 2014 15:07:55 +0000 Subject: [Nek5000-users] turbulent 3d box In-Reply-To: References: , , , , , , , Message-ID: Hi Barak, If the elements are of uniform size in a given direction then, to leading order, the resolution is dx ~ Lx / (N*Ex) where Lx = length in x, Ex=# of elements in x-direction, and N is polynomial order. Technically, the resolution is a bit less -- like (2/pi). There are two errors of primary concern --- approximation error and dispersion. If n=number of points in a given direction (n=N*ex the SEM case), then you have dx=L/n, and Nyquist says you can't resolve wavelengths shorter than 2*dx. This restriction applies to all methods, including Fourier spectral and SEM. For Fourier, all wavenumbers are transported with zero phase error (because of the periodic BCs + fact that they are eigenfunctions of the operators, etc.). For SEM, only 2/pi have diminishing error as N increases, and it is in fact not as small as machine epsilon (as is the case with Fourier spectral, only). However, the SEM is far superior to low-order approaches, and that's where it's strength lies. The primary reason to use SEM over Fourier is when you don't have homogeneous geometries or constant coefficient operators. Paul ________________________________________ From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] Sent: Friday, January 10, 2014 8:30 AM To: nek5000-users at lists.mcs.anl.gov Subject: Re: [Nek5000-users] turbulent 3d box Hi Paul, Thanks for your help till now. Regarding the proper discretization of the 3d turbulent box setup. When simulating using a standard spectral method the smallest scale defines the highest wavenumber kmax. What is its equivalent in SEM? Happy new year 2014, Barak On 01/04/2014 03:40 AM, nek5000-users at lists.mcs.anl.gov wrote: > > Barak, > > I suggest comparing the SIZE files for various examples. From there you should > be able to see how to properly modify SIZE to change the resolution. > > Of course, you'll need to reduce dt to maintain CFL ~ 0.5 > > Paul > > ________________________________________ > From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] > Sent: Sunday, December 22, 2013 4:25 PM > To: nek5000-users at lists.mcs.anl.gov > Subject: Re: [Nek5000-users] turbulent 3d box > > It didn't work (I tried both options). Do you have working example? > (see my previous email and my attachment). > Barak > > On 12/22/2013 11:20 PM, nek5000-users at lists.mcs.anl.gov wrote: >> >> Hi Paul, >> On 12/22/2013 11:14 PM, nek5000-users at lists.mcs.anl.gov wrote: >>> >>> Hi Barak, >>> >>> You can either increase lx1,ly1, lz1 in SIZE and re-make, or you >>> can change nelx,nely,nelz in the .box file. >>> >> Thanks. >>> Did you resolve the issue with the initial condition? >>> >> See my previous email. I have inside further questions. >> Best regards, >> Barak >> >> >>> Paul >>> ________________________________________ >>> From: nek5000-users-bounces at lists.mcs.anl.gov >>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>> Sent: Sunday, December 22, 2013 3:05 PM >>> To: nek5000-users at lists.mcs.anl.gov >>> Subject: Re: [Nek5000-users] turbulent 3d box >>> >>> Hi Paul, >>> Before I run problems with smaller viscosity: how I increase the >>> resolution? and remesh the box? >>> Barak >>> >>> On 12/22/2013 10:24 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>> Hi Barak, >>>> >>>> When I compute the L2 norm of the function, given as: >>>> >>>> v2 = [ sum_i vx_i b_i vx_i + vy_i b_i vy_i + vz_i b_i vz_i >>>> / sum_i b_i ]^(1/2) >>>> >>>> it comes out to ~ 2.23 >>>> >>>> Note that there are some places where ux==2, uy==0, uz==1, >>>> which would give an L2 norm of >>>> >>>> sqrt (2*2 + 0*0 + 1*1) = sqrt(5) > sqrt(3) >>>> >>>> ? >>>> >>>> Paul >>>> >>>> ________________________________________ >>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>> Sent: Sunday, December 22, 2013 11:04 AM >>>> To: nek5000-users at lists.mcs.anl.gov >>>> Subject: Re: [Nek5000-users] turbulent 3d box >>>> >>>> Hi Paul, >>>> My definition for velocity magnitude is: >>>> |v|=sqrt(ux^2+uy^2+uz^2) >>>> so if you see, there are two components in the form: >>>> cos^2(x)+sin^2(x) >>>> etc in each direction >>>> so in fact >>>> |v|=sqrt(3) for any x,y,z. >>>> Isn't correct? >>>> Barak >>>> >>>> On 12/22/2013 05:05 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>> Hi Barak, >>>>> >>>>> If your initial condition is: >>>>> >>>>> ux=(cos(y)+sin(z)) >>>>> uy=(cos(z)+sin(x)) >>>>> uz=(cos(x)+sin(y)) >>>>> >>>>> and your domain is [0,2pi]^3, how is it possible that your velocity >>>>> magnitude >>>>> is less than 2? >>>>> >>>>> >>>>> What is your measure of velocity magnitude? When I compute the L2 >>>>> norm of this initial condition I'm seeing about 2.3+ >>>>> >>>>> Paul >>>>> >>>>> ------------------------------------------------------------------------ >>>>> >>>>> *From:* nek5000-users-bounces at lists.mcs.anl.gov >>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>> *Sent:* Sunday, December 22, 2013 7:53 AM >>>>> *To:* nek5000-users at lists.mcs.anl.gov >>>>> *Subject:* Re: [Nek5000-users] turbulent 3d box >>>>> >>>>> Hi Paul, >>>>> It seems that something does not work, comparing my simulations using a >>>>> standard spectral code (pseudo-spectral). For nu=0.1, I used 16 points >>>>> for each space direction. Now for this case, the nonlinear terms vanish >>>>> (just cancel each other) and the solution is just the ABC flow if you >>>>> set it as initial condition. Then since the forcing is f=nu*ABC the >>>>> dissipation term (Laplacian) dissipation=-nu*ABC and therefore the >>>>> initial value (ABC) remains as it is. If we decrease the viscosity >>>>> above >>>>> the critical value of 1/12 (if I remember correctly) there is a >>>>> bifurcation (Hopf...) and we obtain a new periodic solution (in time), >>>>> where the ABC modes are dominating combined with some high wave numbers >>>>> that are oscillating. >>>>> >>>>> >From my first tests using NEK, I find that the velocity field (for >>>>> nu>1/12) does not agree with the above characteristics. For example, >>>>> the >>>>> max magnitude of the velocity field should be for the ABC flow sqrt(3), >>>>> whereas here I get a value close to 2.5. >>>>> >>>>> Do you have any idea what's wrong? >>>>> If you wish to read some literature about the ABC flow as a forcing for >>>>> Navier Stokes or as a prescribed velocity for generation of magnetic >>>>> field (i.e., kinematic generation of magnetic field MHD): >>>>> >>>>> 1. D. Galloway and U. Frisch. A numerical investigation of magnetic >>>>> field generation in a flow with chaotic streamlines. Geophysical & >>>>> Astrophysical Fluid Dynamics, 29(1):13?18, 1984. >>>>> >>>>> 2. D. Galloway and U. Frisch. Dynamo action in a family of flows with >>>>> chaotic streamlines. >>>>> Geophysical & Astrophysical Fluid Dynamics, 36(1):53?83, 1986. >>>>> >>>>> 3. Podvigina, Pouquet, On the non-linear stability of the 1:1:1 ABC >>>>> flow, >>>>> Phys. D, Vol. 75, 4, 1994. >>>>> >>>>> >>>>> With my best wishes, >>>>> Barak >>>>> >>>>> >>>>> Quoting nek5000-users at lists.mcs.anl.gov >>>>> : >>>>> >>>>>> Hi Barak, >>>>>> >>>>>> Thanks for the note about the ABC flow -- that's very useful. >>>>>> >>>>>> What is your target viscosity? >>>>>> If you want it to be 0.1, then you would set param 2 in the .rea file >>>>>> to be 0.1. >>>>>> Setting param 2 = -0.1 would imply that Re=0.1 or equivalently nu=10. >>>>>> Does this resolve the issue for you? >>>>>> >>>>>> Once it's working we could add it as a documented example in the >>>>>> example >>>>>> suite. >>>>>> >>>>>> Thanks! >>>>>> >>>>>> Paul >>>>>> ________________________________________ >>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>> >>>>>> [nek5000-users-bounces at lists.mcs.anl.gov >>>>>> ] on behalf of >>>>>> nek5000-users at lists.mcs.anl.gov >>>>>> >>>>>> [nek5000-users at lists.mcs.anl.gov >>>>>> ] >>>>>> Sent: Saturday, December 21, 2013 5:24 PM >>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>> >>>>>> Subject: Re: [Nek5000-users] turbulent 3d box >>>>>> >>>>>> Hi Paul, >>>>>> Regarding the 3dbox: >>>>>> The forcing which I propose is known as the ABC flow >>>>>> (Arnold-Beltrami-Childress) and has steady solutions (in the form >>>>>> of ABC >>>>>> flow) with Re=1/nu (nu the viscosity) Re=<12 (in periodic box). >>>>>> The forcing should be in the form: >>>>>> f=Re*ABC in order to balance the dissipation term. >>>>>> This settings can serve as a benchmark for pure hydro/mhd problems. >>>>>> >>>>>> I tried to fix the example which you have sent me, but I don't succeed >>>>>> retreiving the expected values. >>>>>> I attach the relevant files( tarball file). >>>>>> Best regards, >>>>>> Barak >>>>>> >>>>>> >>>>>> >>>>>> On 12/18/2013 03:29 AM, nek5000-users at lists.mcs.anl.gov >>>>>> wrote: >>>>>> >>>>>>> Hi Barak, >>>>>>> >>>>>>> I added a 3d periodic box under "3dbox" in the examples >>>>>>> directory. >>>>>>> >>>>>>> Paul >>>>>>> >>>>>>> >>>>>>> Dear nek's, >>>>>>> I would like to run the following problem: >>>>>>> a 3D periodic box, small viscosity and the following forcing: >>>>>>> >>>>>>> fx=cos(y)+sin(z) >>>>>>> fy=cos(z)+sin(x) >>>>>>> fz=cos(x)+sin(y) >>>>>>> >>>>>>> Do you have a similar example? >>>>>>> >>>>>>> Many thanks, >>>>>>> Barak >>>>>>> >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl >>>>>> .govhttps://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > _______________________________________________ Nek5000-users mailing list Nek5000-users at lists.mcs.anl.gov https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users From nek5000-users at lists.mcs.anl.gov Sat Jan 11 04:59:46 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Sat, 11 Jan 2014 12:59:46 +0200 Subject: [Nek5000-users] turbulent 3d box In-Reply-To: References: , , , , , , Message-ID: Dear Paul, Thank you for the information. I am a bit unfamiliar with the basic knowledge in SEM. Could you recommend me a nice short introduction for the theory? especially that deals with the issues below. Many thanks, Barak On 01/10/2014 05:07 PM, nek5000-users at lists.mcs.anl.gov wrote: > > Hi Barak, > > If the elements are of uniform size in a given direction then, to leading order, the > resolution is > > dx ~ Lx / (N*Ex) > > where Lx = length in x, Ex=# of elements in x-direction, and N is polynomial order. > > Technically, the resolution is a bit less -- like (2/pi). > > There are two errors of primary concern --- approximation error and dispersion. > > If n=number of points in a given direction (n=N*ex the SEM case), then you have dx=L/n, > and Nyquist says you can't resolve wavelengths shorter than 2*dx. This restriction applies > to all methods, including Fourier spectral and SEM. > > For Fourier, all wavenumbers are transported with zero phase error (because of the periodic > BCs + fact that they are eigenfunctions of the operators, etc.). > > For SEM, only 2/pi have diminishing error as N increases, and it is in fact not as small > as machine epsilon (as is the case with Fourier spectral, only). However, the SEM is > far superior to low-order approaches, and that's where it's strength lies. The primary > reason to use SEM over Fourier is when you don't have homogeneous geometries or > constant coefficient operators. > > Paul > > ________________________________________ > From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] > Sent: Friday, January 10, 2014 8:30 AM > To: nek5000-users at lists.mcs.anl.gov > Subject: Re: [Nek5000-users] turbulent 3d box > > Hi Paul, > Thanks for your help till now. > Regarding the proper discretization of the 3d turbulent box setup. When > simulating using a standard spectral method the smallest scale defines > the highest wavenumber kmax. What is its equivalent in SEM? > Happy new year 2014, > Barak > > On 01/04/2014 03:40 AM, nek5000-users at lists.mcs.anl.gov wrote: >> >> Barak, >> >> I suggest comparing the SIZE files for various examples. From there you should >> be able to see how to properly modify SIZE to change the resolution. >> >> Of course, you'll need to reduce dt to maintain CFL ~ 0.5 >> >> Paul >> >> ________________________________________ >> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >> Sent: Sunday, December 22, 2013 4:25 PM >> To: nek5000-users at lists.mcs.anl.gov >> Subject: Re: [Nek5000-users] turbulent 3d box >> >> It didn't work (I tried both options). Do you have working example? >> (see my previous email and my attachment). >> Barak >> >> On 12/22/2013 11:20 PM, nek5000-users at lists.mcs.anl.gov wrote: >>> >>> Hi Paul, >>> On 12/22/2013 11:14 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>> Hi Barak, >>>> >>>> You can either increase lx1,ly1, lz1 in SIZE and re-make, or you >>>> can change nelx,nely,nelz in the .box file. >>>> >>> Thanks. >>>> Did you resolve the issue with the initial condition? >>>> >>> See my previous email. I have inside further questions. >>> Best regards, >>> Barak >>> >>> >>>> Paul >>>> ________________________________________ >>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>> Sent: Sunday, December 22, 2013 3:05 PM >>>> To: nek5000-users at lists.mcs.anl.gov >>>> Subject: Re: [Nek5000-users] turbulent 3d box >>>> >>>> Hi Paul, >>>> Before I run problems with smaller viscosity: how I increase the >>>> resolution? and remesh the box? >>>> Barak >>>> >>>> On 12/22/2013 10:24 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>> Hi Barak, >>>>> >>>>> When I compute the L2 norm of the function, given as: >>>>> >>>>> v2 = [ sum_i vx_i b_i vx_i + vy_i b_i vy_i + vz_i b_i vz_i >>>>> / sum_i b_i ]^(1/2) >>>>> >>>>> it comes out to ~ 2.23 >>>>> >>>>> Note that there are some places where ux==2, uy==0, uz==1, >>>>> which would give an L2 norm of >>>>> >>>>> sqrt (2*2 + 0*0 + 1*1) = sqrt(5) > sqrt(3) >>>>> >>>>> ? >>>>> >>>>> Paul >>>>> >>>>> ________________________________________ >>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>> Sent: Sunday, December 22, 2013 11:04 AM >>>>> To: nek5000-users at lists.mcs.anl.gov >>>>> Subject: Re: [Nek5000-users] turbulent 3d box >>>>> >>>>> Hi Paul, >>>>> My definition for velocity magnitude is: >>>>> |v|=sqrt(ux^2+uy^2+uz^2) >>>>> so if you see, there are two components in the form: >>>>> cos^2(x)+sin^2(x) >>>>> etc in each direction >>>>> so in fact >>>>> |v|=sqrt(3) for any x,y,z. >>>>> Isn't correct? >>>>> Barak >>>>> >>>>> On 12/22/2013 05:05 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>> Hi Barak, >>>>>> >>>>>> If your initial condition is: >>>>>> >>>>>> ux=(cos(y)+sin(z)) >>>>>> uy=(cos(z)+sin(x)) >>>>>> uz=(cos(x)+sin(y)) >>>>>> >>>>>> and your domain is [0,2pi]^3, how is it possible that your velocity >>>>>> magnitude >>>>>> is less than 2? >>>>>> >>>>>> >>>>>> What is your measure of velocity magnitude? When I compute the L2 >>>>>> norm of this initial condition I'm seeing about 2.3+ >>>>>> >>>>>> Paul >>>>>> >>>>>> ------------------------------------------------------------------------ >>>>>> >>>>>> *From:* nek5000-users-bounces at lists.mcs.anl.gov >>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>> *Sent:* Sunday, December 22, 2013 7:53 AM >>>>>> *To:* nek5000-users at lists.mcs.anl.gov >>>>>> *Subject:* Re: [Nek5000-users] turbulent 3d box >>>>>> >>>>>> Hi Paul, >>>>>> It seems that something does not work, comparing my simulations using a >>>>>> standard spectral code (pseudo-spectral). For nu=0.1, I used 16 points >>>>>> for each space direction. Now for this case, the nonlinear terms vanish >>>>>> (just cancel each other) and the solution is just the ABC flow if you >>>>>> set it as initial condition. Then since the forcing is f=nu*ABC the >>>>>> dissipation term (Laplacian) dissipation=-nu*ABC and therefore the >>>>>> initial value (ABC) remains as it is. If we decrease the viscosity >>>>>> above >>>>>> the critical value of 1/12 (if I remember correctly) there is a >>>>>> bifurcation (Hopf...) and we obtain a new periodic solution (in time), >>>>>> where the ABC modes are dominating combined with some high wave numbers >>>>>> that are oscillating. >>>>>> >>>>>> >From my first tests using NEK, I find that the velocity field (for >>>>>> nu>1/12) does not agree with the above characteristics. For example, >>>>>> the >>>>>> max magnitude of the velocity field should be for the ABC flow sqrt(3), >>>>>> whereas here I get a value close to 2.5. >>>>>> >>>>>> Do you have any idea what's wrong? >>>>>> If you wish to read some literature about the ABC flow as a forcing for >>>>>> Navier Stokes or as a prescribed velocity for generation of magnetic >>>>>> field (i.e., kinematic generation of magnetic field MHD): >>>>>> >>>>>> 1. D. Galloway and U. Frisch. A numerical investigation of magnetic >>>>>> field generation in a flow with chaotic streamlines. Geophysical & >>>>>> Astrophysical Fluid Dynamics, 29(1):13?18, 1984. >>>>>> >>>>>> 2. D. Galloway and U. Frisch. Dynamo action in a family of flows with >>>>>> chaotic streamlines. >>>>>> Geophysical & Astrophysical Fluid Dynamics, 36(1):53?83, 1986. >>>>>> >>>>>> 3. Podvigina, Pouquet, On the non-linear stability of the 1:1:1 ABC >>>>>> flow, >>>>>> Phys. D, Vol. 75, 4, 1994. >>>>>> >>>>>> >>>>>> With my best wishes, >>>>>> Barak >>>>>> >>>>>> >>>>>> Quoting nek5000-users at lists.mcs.anl.gov >>>>>> : >>>>>> >>>>>>> Hi Barak, >>>>>>> >>>>>>> Thanks for the note about the ABC flow -- that's very useful. >>>>>>> >>>>>>> What is your target viscosity? >>>>>>> If you want it to be 0.1, then you would set param 2 in the .rea file >>>>>>> to be 0.1. >>>>>>> Setting param 2 = -0.1 would imply that Re=0.1 or equivalently nu=10. >>>>>>> Does this resolve the issue for you? >>>>>>> >>>>>>> Once it's working we could add it as a documented example in the >>>>>>> example >>>>>>> suite. >>>>>>> >>>>>>> Thanks! >>>>>>> >>>>>>> Paul >>>>>>> ________________________________________ >>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>> >>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov >>>>>>> ] on behalf of >>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>> >>>>>>> [nek5000-users at lists.mcs.anl.gov >>>>>>> ] >>>>>>> Sent: Saturday, December 21, 2013 5:24 PM >>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>> >>>>>>> Subject: Re: [Nek5000-users] turbulent 3d box >>>>>>> >>>>>>> Hi Paul, >>>>>>> Regarding the 3dbox: >>>>>>> The forcing which I propose is known as the ABC flow >>>>>>> (Arnold-Beltrami-Childress) and has steady solutions (in the form >>>>>>> of ABC >>>>>>> flow) with Re=1/nu (nu the viscosity) Re=<12 (in periodic box). >>>>>>> The forcing should be in the form: >>>>>>> f=Re*ABC in order to balance the dissipation term. >>>>>>> This settings can serve as a benchmark for pure hydro/mhd problems. >>>>>>> >>>>>>> I tried to fix the example which you have sent me, but I don't succeed >>>>>>> retreiving the expected values. >>>>>>> I attach the relevant files( tarball file). >>>>>>> Best regards, >>>>>>> Barak >>>>>>> >>>>>>> >>>>>>> >>>>>>> On 12/18/2013 03:29 AM, nek5000-users at lists.mcs.anl.gov >>>>>>> wrote: >>>>>>> >>>>>>>> Hi Barak, >>>>>>>> >>>>>>>> I added a 3d periodic box under "3dbox" in the examples >>>>>>>> directory. >>>>>>>> >>>>>>>> Paul >>>>>>>> >>>>>>>> >>>>>>>> Dear nek's, >>>>>>>> I would like to run the following problem: >>>>>>>> a 3D periodic box, small viscosity and the following forcing: >>>>>>>> >>>>>>>> fx=cos(y)+sin(z) >>>>>>>> fy=cos(z)+sin(x) >>>>>>>> fz=cos(x)+sin(y) >>>>>>>> >>>>>>>> Do you have a similar example? >>>>>>>> >>>>>>>> Many thanks, >>>>>>>> Barak >>>>>>>> >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl >>>>>>> .govhttps://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > From nek5000-users at lists.mcs.anl.gov Sat Jan 11 22:23:52 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Sun, 12 Jan 2014 09:53:52 +0530 Subject: [Nek5000-users] Possible to read solution *.fld# or *.f# files in matlab ? Message-ID: Hello Is it possible to read the nek solution files in matlab ? I want to do some postprocessing. If yes, are there any examples ? Thanks praveen -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Sun Jan 12 14:14:53 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Sun, 12 Jan 2014 21:14:53 +0100 Subject: [Nek5000-users] turbulent 3d box In-Reply-To: References: Message-ID: Hi, This is a very nice book about SEM. It could be a good start, if you already know something about finite element method and spectral method. http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780198528692.001.0001/acprof-9780198528692 The second book is by CHQZ, a classic of spectral method, but also talks about SEM. http://www.springer.com/mathematics/computational+science+%26+engineering/book/978-3-540-30727-3 Good lecture! Tubois On Sat, Jan 11, 2014 at 11:59 AM, wrote: > Dear Paul, > Thank you for the information. I am a bit unfamiliar with the basic > knowledge in SEM. Could you recommend me a nice short introduction for the > theory? especially that deals with the issues below. > > Many thanks, > Barak > > > On 01/10/2014 05:07 PM, nek5000-users at lists.mcs.anl.gov wrote: > >> >> Hi Barak, >> >> If the elements are of uniform size in a given direction then, to leading >> order, the >> resolution is >> >> dx ~ Lx / (N*Ex) >> >> where Lx = length in x, Ex=# of elements in x-direction, and N is >> polynomial order. >> >> Technically, the resolution is a bit less -- like (2/pi). >> >> There are two errors of primary concern --- approximation error and >> dispersion. >> >> If n=number of points in a given direction (n=N*ex the SEM case), then >> you have dx=L/n, >> and Nyquist says you can't resolve wavelengths shorter than 2*dx. This >> restriction applies >> to all methods, including Fourier spectral and SEM. >> >> For Fourier, all wavenumbers are transported with zero phase error >> (because of the periodic >> BCs + fact that they are eigenfunctions of the operators, etc.). >> >> For SEM, only 2/pi have diminishing error as N increases, and it is in >> fact not as small >> as machine epsilon (as is the case with Fourier spectral, only). >> However, the SEM is >> far superior to low-order approaches, and that's where it's strength >> lies. The primary >> reason to use SEM over Fourier is when you don't have homogeneous >> geometries or >> constant coefficient operators. >> >> Paul >> >> ________________________________________ >> From: nek5000-users-bounces at lists.mcs.anl.gov [ >> nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >> Sent: Friday, January 10, 2014 8:30 AM >> To: nek5000-users at lists.mcs.anl.gov >> Subject: Re: [Nek5000-users] turbulent 3d box >> >> Hi Paul, >> Thanks for your help till now. >> Regarding the proper discretization of the 3d turbulent box setup. When >> simulating using a standard spectral method the smallest scale defines >> the highest wavenumber kmax. What is its equivalent in SEM? >> Happy new year 2014, >> Barak >> >> On 01/04/2014 03:40 AM, nek5000-users at lists.mcs.anl.gov wrote: >> >>> >>> Barak, >>> >>> I suggest comparing the SIZE files for various examples. From there you >>> should >>> be able to see how to properly modify SIZE to change the resolution. >>> >>> Of course, you'll need to reduce dt to maintain CFL ~ 0.5 >>> >>> Paul >>> >>> ________________________________________ >>> From: nek5000-users-bounces at lists.mcs.anl.gov [ >>> nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>> Sent: Sunday, December 22, 2013 4:25 PM >>> To: nek5000-users at lists.mcs.anl.gov >>> Subject: Re: [Nek5000-users] turbulent 3d box >>> >>> It didn't work (I tried both options). Do you have working example? >>> (see my previous email and my attachment). >>> Barak >>> >>> On 12/22/2013 11:20 PM, nek5000-users at lists.mcs.anl.gov wrote: >>> >>>> >>>> Hi Paul, >>>> On 12/22/2013 11:14 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> >>>>> Hi Barak, >>>>> >>>>> You can either increase lx1,ly1, lz1 in SIZE and re-make, or you >>>>> can change nelx,nely,nelz in the .box file. >>>>> >>>>> Thanks. >>>> >>>>> Did you resolve the issue with the initial condition? >>>>> >>>>> See my previous email. I have inside further questions. >>>> Best regards, >>>> Barak >>>> >>>> >>>> Paul >>>>> ________________________________________ >>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>> Sent: Sunday, December 22, 2013 3:05 PM >>>>> To: nek5000-users at lists.mcs.anl.gov >>>>> Subject: Re: [Nek5000-users] turbulent 3d box >>>>> >>>>> Hi Paul, >>>>> Before I run problems with smaller viscosity: how I increase the >>>>> resolution? and remesh the box? >>>>> Barak >>>>> >>>>> On 12/22/2013 10:24 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>>> >>>>>> Hi Barak, >>>>>> >>>>>> When I compute the L2 norm of the function, given as: >>>>>> >>>>>> v2 = [ sum_i vx_i b_i vx_i + vy_i b_i vy_i + vz_i b_i vz_i >>>>>> / sum_i b_i ]^(1/2) >>>>>> >>>>>> it comes out to ~ 2.23 >>>>>> >>>>>> Note that there are some places where ux==2, uy==0, uz==1, >>>>>> which would give an L2 norm of >>>>>> >>>>>> sqrt (2*2 + 0*0 + 1*1) = sqrt(5) > sqrt(3) >>>>>> >>>>>> ? >>>>>> >>>>>> Paul >>>>>> >>>>>> ________________________________________ >>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>> Sent: Sunday, December 22, 2013 11:04 AM >>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>> Subject: Re: [Nek5000-users] turbulent 3d box >>>>>> >>>>>> Hi Paul, >>>>>> My definition for velocity magnitude is: >>>>>> |v|=sqrt(ux^2+uy^2+uz^2) >>>>>> so if you see, there are two components in the form: >>>>>> cos^2(x)+sin^2(x) >>>>>> etc in each direction >>>>>> so in fact >>>>>> |v|=sqrt(3) for any x,y,z. >>>>>> Isn't correct? >>>>>> Barak >>>>>> >>>>>> On 12/22/2013 05:05 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>>> >>>>>>> Hi Barak, >>>>>>> >>>>>>> If your initial condition is: >>>>>>> >>>>>>> ux=(cos(y)+sin(z)) >>>>>>> uy=(cos(z)+sin(x)) >>>>>>> uz=(cos(x)+sin(y)) >>>>>>> >>>>>>> and your domain is [0,2pi]^3, how is it possible that your velocity >>>>>>> magnitude >>>>>>> is less than 2? >>>>>>> >>>>>>> >>>>>>> What is your measure of velocity magnitude? When I compute the L2 >>>>>>> norm of this initial condition I'm seeing about 2.3+ >>>>>>> >>>>>>> Paul >>>>>>> >>>>>>> ------------------------------------------------------------ >>>>>>> ------------ >>>>>>> >>>>>>> *From:* nek5000-users-bounces at lists.mcs.anl.gov >>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>>> *Sent:* Sunday, December 22, 2013 7:53 AM >>>>>>> *To:* nek5000-users at lists.mcs.anl.gov >>>>>>> *Subject:* Re: [Nek5000-users] turbulent 3d box >>>>>>> >>>>>>> Hi Paul, >>>>>>> It seems that something does not work, comparing my simulations >>>>>>> using a >>>>>>> standard spectral code (pseudo-spectral). For nu=0.1, I used 16 >>>>>>> points >>>>>>> for each space direction. Now for this case, the nonlinear terms >>>>>>> vanish >>>>>>> (just cancel each other) and the solution is just the ABC flow if you >>>>>>> set it as initial condition. Then since the forcing is f=nu*ABC the >>>>>>> dissipation term (Laplacian) dissipation=-nu*ABC and therefore the >>>>>>> initial value (ABC) remains as it is. If we decrease the viscosity >>>>>>> above >>>>>>> the critical value of 1/12 (if I remember correctly) there is a >>>>>>> bifurcation (Hopf...) and we obtain a new periodic solution (in >>>>>>> time), >>>>>>> where the ABC modes are dominating combined with some high wave >>>>>>> numbers >>>>>>> that are oscillating. >>>>>>> >>>>>>> >From my first tests using NEK, I find that the velocity field >>>>>>> (for >>>>>>> nu>1/12) does not agree with the above characteristics. For example, >>>>>>> the >>>>>>> max magnitude of the velocity field should be for the ABC flow >>>>>>> sqrt(3), >>>>>>> whereas here I get a value close to 2.5. >>>>>>> >>>>>>> Do you have any idea what's wrong? >>>>>>> If you wish to read some literature about the ABC flow as a forcing >>>>>>> for >>>>>>> Navier Stokes or as a prescribed velocity for generation of magnetic >>>>>>> field (i.e., kinematic generation of magnetic field MHD): >>>>>>> >>>>>>> 1. D. Galloway and U. Frisch. A numerical investigation of magnetic >>>>>>> field generation in a flow with chaotic streamlines. Geophysical & >>>>>>> Astrophysical Fluid Dynamics, 29(1):13?18, 1984. >>>>>>> >>>>>>> 2. D. Galloway and U. Frisch. Dynamo action in a family of flows with >>>>>>> chaotic streamlines. >>>>>>> Geophysical & Astrophysical Fluid Dynamics, 36(1):53?83, 1986. >>>>>>> >>>>>>> 3. Podvigina, Pouquet, On the non-linear stability of the 1:1:1 ABC >>>>>>> flow, >>>>>>> Phys. D, Vol. 75, 4, 1994. >>>>>>> >>>>>>> >>>>>>> With my best wishes, >>>>>>> Barak >>>>>>> >>>>>>> >>>>>>> Quoting nek5000-users at lists.mcs.anl.gov >>>>>>> : >>>>>>> >>>>>>> Hi Barak, >>>>>>>> >>>>>>>> Thanks for the note about the ABC flow -- that's very useful. >>>>>>>> >>>>>>>> What is your target viscosity? >>>>>>>> If you want it to be 0.1, then you would set param 2 in the .rea >>>>>>>> file >>>>>>>> to be 0.1. >>>>>>>> Setting param 2 = -0.1 would imply that Re=0.1 or equivalently >>>>>>>> nu=10. >>>>>>>> Does this resolve the issue for you? >>>>>>>> >>>>>>>> Once it's working we could add it as a documented example in the >>>>>>>> example >>>>>>>> suite. >>>>>>>> >>>>>>>> Thanks! >>>>>>>> >>>>>>>> Paul >>>>>>>> ________________________________________ >>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>> >>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>> ] on behalf of >>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>> >>>>>>>> [nek5000-users at lists.mcs.anl.gov >>>>>>>> ] >>>>>>>> Sent: Saturday, December 21, 2013 5:24 PM >>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>> >>>>>>>> Subject: Re: [Nek5000-users] turbulent 3d box >>>>>>>> >>>>>>>> Hi Paul, >>>>>>>> Regarding the 3dbox: >>>>>>>> The forcing which I propose is known as the ABC flow >>>>>>>> (Arnold-Beltrami-Childress) and has steady solutions (in the form >>>>>>>> of ABC >>>>>>>> flow) with Re=1/nu (nu the viscosity) Re=<12 (in periodic box). >>>>>>>> The forcing should be in the form: >>>>>>>> f=Re*ABC in order to balance the dissipation term. >>>>>>>> This settings can serve as a benchmark for pure hydro/mhd problems. >>>>>>>> >>>>>>>> I tried to fix the example which you have sent me, but I don't >>>>>>>> succeed >>>>>>>> retreiving the expected values. >>>>>>>> I attach the relevant files( tarball file). >>>>>>>> Best regards, >>>>>>>> Barak >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> On 12/18/2013 03:29 AM, nek5000-users at lists.mcs.anl.gov >>>>>>>> wrote: >>>>>>>> >>>>>>>> Hi Barak, >>>>>>>>> >>>>>>>>> I added a 3d periodic box under "3dbox" in the examples >>>>>>>>> directory. >>>>>>>>> >>>>>>>>> Paul >>>>>>>>> >>>>>>>>> >>>>>>>>> Dear nek's, >>>>>>>>> I would like to run the following problem: >>>>>>>>> a 3D periodic box, small viscosity and the following forcing: >>>>>>>>> >>>>>>>>> fx=cos(y)+sin(z) >>>>>>>>> fy=cos(z)+sin(x) >>>>>>>>> fz=cos(x)+sin(y) >>>>>>>>> >>>>>>>>> Do you have a similar example? >>>>>>>>> >>>>>>>>> Many thanks, >>>>>>>>> Barak >>>>>>>>> >>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl >>>>>>>> .govhttps://lists.mcs. >>>>>>>> anl.gov/mailman/listinfo/nek5000-users >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > -- Ecole Polytechnique Email; zhenlan.gao at polytechnique.edu zhenlan.gao at gadz.org Addresse: Chambre 5017, Maison des Arts et M?tiers, 1, avenue Pierre Mass? 75014 Paris, France -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Sun Jan 12 14:43:15 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Sun, 12 Jan 2014 20:43:15 +0000 Subject: [Nek5000-users] turbulent 3d box In-Reply-To: References: , , , , , , , Message-ID: Barak, Most of this is covered in Chap. 3 of Deville, Fischer, & Mund, High Order Methods for Incompressible Flow. As Tubois indicates, Canuto, Hussaini, Quarteroni & Zang - either first or 2nd edition also cover these topics in varied levels of detail. Paul ________________________________________ From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] Sent: Saturday, January 11, 2014 4:59 AM To: nek5000-users at lists.mcs.anl.gov Subject: Re: [Nek5000-users] turbulent 3d box Dear Paul, Thank you for the information. I am a bit unfamiliar with the basic knowledge in SEM. Could you recommend me a nice short introduction for the theory? especially that deals with the issues below. Many thanks, Barak On 01/10/2014 05:07 PM, nek5000-users at lists.mcs.anl.gov wrote: > > Hi Barak, > > If the elements are of uniform size in a given direction then, to leading order, the > resolution is > > dx ~ Lx / (N*Ex) > > where Lx = length in x, Ex=# of elements in x-direction, and N is polynomial order. > > Technically, the resolution is a bit less -- like (2/pi). > > There are two errors of primary concern --- approximation error and dispersion. > > If n=number of points in a given direction (n=N*ex the SEM case), then you have dx=L/n, > and Nyquist says you can't resolve wavelengths shorter than 2*dx. This restriction applies > to all methods, including Fourier spectral and SEM. > > For Fourier, all wavenumbers are transported with zero phase error (because of the periodic > BCs + fact that they are eigenfunctions of the operators, etc.). > > For SEM, only 2/pi have diminishing error as N increases, and it is in fact not as small > as machine epsilon (as is the case with Fourier spectral, only). However, the SEM is > far superior to low-order approaches, and that's where it's strength lies. The primary > reason to use SEM over Fourier is when you don't have homogeneous geometries or > constant coefficient operators. > > Paul > > ________________________________________ > From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] > Sent: Friday, January 10, 2014 8:30 AM > To: nek5000-users at lists.mcs.anl.gov > Subject: Re: [Nek5000-users] turbulent 3d box > > Hi Paul, > Thanks for your help till now. > Regarding the proper discretization of the 3d turbulent box setup. When > simulating using a standard spectral method the smallest scale defines > the highest wavenumber kmax. What is its equivalent in SEM? > Happy new year 2014, > Barak > > On 01/04/2014 03:40 AM, nek5000-users at lists.mcs.anl.gov wrote: >> >> Barak, >> >> I suggest comparing the SIZE files for various examples. From there you should >> be able to see how to properly modify SIZE to change the resolution. >> >> Of course, you'll need to reduce dt to maintain CFL ~ 0.5 >> >> Paul >> >> ________________________________________ >> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >> Sent: Sunday, December 22, 2013 4:25 PM >> To: nek5000-users at lists.mcs.anl.gov >> Subject: Re: [Nek5000-users] turbulent 3d box >> >> It didn't work (I tried both options). Do you have working example? >> (see my previous email and my attachment). >> Barak >> >> On 12/22/2013 11:20 PM, nek5000-users at lists.mcs.anl.gov wrote: >>> >>> Hi Paul, >>> On 12/22/2013 11:14 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>> Hi Barak, >>>> >>>> You can either increase lx1,ly1, lz1 in SIZE and re-make, or you >>>> can change nelx,nely,nelz in the .box file. >>>> >>> Thanks. >>>> Did you resolve the issue with the initial condition? >>>> >>> See my previous email. I have inside further questions. >>> Best regards, >>> Barak >>> >>> >>>> Paul >>>> ________________________________________ >>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>> Sent: Sunday, December 22, 2013 3:05 PM >>>> To: nek5000-users at lists.mcs.anl.gov >>>> Subject: Re: [Nek5000-users] turbulent 3d box >>>> >>>> Hi Paul, >>>> Before I run problems with smaller viscosity: how I increase the >>>> resolution? and remesh the box? >>>> Barak >>>> >>>> On 12/22/2013 10:24 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>> Hi Barak, >>>>> >>>>> When I compute the L2 norm of the function, given as: >>>>> >>>>> v2 = [ sum_i vx_i b_i vx_i + vy_i b_i vy_i + vz_i b_i vz_i >>>>> / sum_i b_i ]^(1/2) >>>>> >>>>> it comes out to ~ 2.23 >>>>> >>>>> Note that there are some places where ux==2, uy==0, uz==1, >>>>> which would give an L2 norm of >>>>> >>>>> sqrt (2*2 + 0*0 + 1*1) = sqrt(5) > sqrt(3) >>>>> >>>>> ? >>>>> >>>>> Paul >>>>> >>>>> ________________________________________ >>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>> Sent: Sunday, December 22, 2013 11:04 AM >>>>> To: nek5000-users at lists.mcs.anl.gov >>>>> Subject: Re: [Nek5000-users] turbulent 3d box >>>>> >>>>> Hi Paul, >>>>> My definition for velocity magnitude is: >>>>> |v|=sqrt(ux^2+uy^2+uz^2) >>>>> so if you see, there are two components in the form: >>>>> cos^2(x)+sin^2(x) >>>>> etc in each direction >>>>> so in fact >>>>> |v|=sqrt(3) for any x,y,z. >>>>> Isn't correct? >>>>> Barak >>>>> >>>>> On 12/22/2013 05:05 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>> Hi Barak, >>>>>> >>>>>> If your initial condition is: >>>>>> >>>>>> ux=(cos(y)+sin(z)) >>>>>> uy=(cos(z)+sin(x)) >>>>>> uz=(cos(x)+sin(y)) >>>>>> >>>>>> and your domain is [0,2pi]^3, how is it possible that your velocity >>>>>> magnitude >>>>>> is less than 2? >>>>>> >>>>>> >>>>>> What is your measure of velocity magnitude? When I compute the L2 >>>>>> norm of this initial condition I'm seeing about 2.3+ >>>>>> >>>>>> Paul >>>>>> >>>>>> ------------------------------------------------------------------------ >>>>>> >>>>>> *From:* nek5000-users-bounces at lists.mcs.anl.gov >>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>> *Sent:* Sunday, December 22, 2013 7:53 AM >>>>>> *To:* nek5000-users at lists.mcs.anl.gov >>>>>> *Subject:* Re: [Nek5000-users] turbulent 3d box >>>>>> >>>>>> Hi Paul, >>>>>> It seems that something does not work, comparing my simulations using a >>>>>> standard spectral code (pseudo-spectral). For nu=0.1, I used 16 points >>>>>> for each space direction. Now for this case, the nonlinear terms vanish >>>>>> (just cancel each other) and the solution is just the ABC flow if you >>>>>> set it as initial condition. Then since the forcing is f=nu*ABC the >>>>>> dissipation term (Laplacian) dissipation=-nu*ABC and therefore the >>>>>> initial value (ABC) remains as it is. If we decrease the viscosity >>>>>> above >>>>>> the critical value of 1/12 (if I remember correctly) there is a >>>>>> bifurcation (Hopf...) and we obtain a new periodic solution (in time), >>>>>> where the ABC modes are dominating combined with some high wave numbers >>>>>> that are oscillating. >>>>>> >>>>>> >From my first tests using NEK, I find that the velocity field (for >>>>>> nu>1/12) does not agree with the above characteristics. For example, >>>>>> the >>>>>> max magnitude of the velocity field should be for the ABC flow sqrt(3), >>>>>> whereas here I get a value close to 2.5. >>>>>> >>>>>> Do you have any idea what's wrong? >>>>>> If you wish to read some literature about the ABC flow as a forcing for >>>>>> Navier Stokes or as a prescribed velocity for generation of magnetic >>>>>> field (i.e., kinematic generation of magnetic field MHD): >>>>>> >>>>>> 1. D. Galloway and U. Frisch. A numerical investigation of magnetic >>>>>> field generation in a flow with chaotic streamlines. Geophysical & >>>>>> Astrophysical Fluid Dynamics, 29(1):13?18, 1984. >>>>>> >>>>>> 2. D. Galloway and U. Frisch. Dynamo action in a family of flows with >>>>>> chaotic streamlines. >>>>>> Geophysical & Astrophysical Fluid Dynamics, 36(1):53?83, 1986. >>>>>> >>>>>> 3. Podvigina, Pouquet, On the non-linear stability of the 1:1:1 ABC >>>>>> flow, >>>>>> Phys. D, Vol. 75, 4, 1994. >>>>>> >>>>>> >>>>>> With my best wishes, >>>>>> Barak >>>>>> >>>>>> >>>>>> Quoting nek5000-users at lists.mcs.anl.gov >>>>>> : >>>>>> >>>>>>> Hi Barak, >>>>>>> >>>>>>> Thanks for the note about the ABC flow -- that's very useful. >>>>>>> >>>>>>> What is your target viscosity? >>>>>>> If you want it to be 0.1, then you would set param 2 in the .rea file >>>>>>> to be 0.1. >>>>>>> Setting param 2 = -0.1 would imply that Re=0.1 or equivalently nu=10. >>>>>>> Does this resolve the issue for you? >>>>>>> >>>>>>> Once it's working we could add it as a documented example in the >>>>>>> example >>>>>>> suite. >>>>>>> >>>>>>> Thanks! >>>>>>> >>>>>>> Paul >>>>>>> ________________________________________ >>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>> >>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov >>>>>>> ] on behalf of >>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>> >>>>>>> [nek5000-users at lists.mcs.anl.gov >>>>>>> ] >>>>>>> Sent: Saturday, December 21, 2013 5:24 PM >>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>> >>>>>>> Subject: Re: [Nek5000-users] turbulent 3d box >>>>>>> >>>>>>> Hi Paul, >>>>>>> Regarding the 3dbox: >>>>>>> The forcing which I propose is known as the ABC flow >>>>>>> (Arnold-Beltrami-Childress) and has steady solutions (in the form >>>>>>> of ABC >>>>>>> flow) with Re=1/nu (nu the viscosity) Re=<12 (in periodic box). >>>>>>> The forcing should be in the form: >>>>>>> f=Re*ABC in order to balance the dissipation term. >>>>>>> This settings can serve as a benchmark for pure hydro/mhd problems. >>>>>>> >>>>>>> I tried to fix the example which you have sent me, but I don't succeed >>>>>>> retreiving the expected values. >>>>>>> I attach the relevant files( tarball file). >>>>>>> Best regards, >>>>>>> Barak >>>>>>> >>>>>>> >>>>>>> >>>>>>> On 12/18/2013 03:29 AM, nek5000-users at lists.mcs.anl.gov >>>>>>> wrote: >>>>>>> >>>>>>>> Hi Barak, >>>>>>>> >>>>>>>> I added a 3d periodic box under "3dbox" in the examples >>>>>>>> directory. >>>>>>>> >>>>>>>> Paul >>>>>>>> >>>>>>>> >>>>>>>> Dear nek's, >>>>>>>> I would like to run the following problem: >>>>>>>> a 3D periodic box, small viscosity and the following forcing: >>>>>>>> >>>>>>>> fx=cos(y)+sin(z) >>>>>>>> fy=cos(z)+sin(x) >>>>>>>> fz=cos(x)+sin(y) >>>>>>>> >>>>>>>> Do you have a similar example? >>>>>>>> >>>>>>>> Many thanks, >>>>>>>> Barak >>>>>>>> >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl >>>>>>> .govhttps://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > _______________________________________________ Nek5000-users mailing list Nek5000-users at lists.mcs.anl.gov https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users From nek5000-users at lists.mcs.anl.gov Mon Jan 13 03:35:13 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Mon, 13 Jan 2014 10:35:13 +0100 Subject: [Nek5000-users] Creating a Mesh Message-ID: Hi Can some one please help me in this because I am new to nek 1) How can I create a .rea for a specific geometry say ' A sudden expansion pipe ' or a ' Diverging pipe ' 2) What tool I should use to create that mesh. Thank you kamal From nek5000-users at lists.mcs.anl.gov Mon Jan 13 08:49:56 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Mon, 13 Jan 2014 15:49:56 +0100 Subject: [Nek5000-users] Problem in 2d pipe simulation Message-ID: Hi, I created my .box file, with help of genbox I created .rea file. later I created a .usr and SIZE file. I have attached all the files I used with this mail I launched the simulation and I got this error ***************************************************************** /----------------------------------------------------------\\ | _ __ ______ __ __ ______ ____ ____ ____ | | / | / // ____// //_/ / ____/ / __ \\ / __ \\ / __ \\ | | / |/ // __/ / ,< /___ \\ / / / // / / // / / / | | / /| // /___ / /| | ____/ / / /_/ // /_/ // /_/ / | | /_/ |_//_____//_/ |_|/_____/ \\____/ \\____/ \\____/ | | | |----------------------------------------------------------| | | | NEK5000: Open Source Spectral Element Solver | | COPYRIGHT (c) 2008-2010 UCHICAGO ARGONNE, LLC | | Version: 1.0rc1 / SVN r982 | | Web: http://nek5000.mcs.anl.gov | | | \\----------------------------------------------------------/ Number of processors: 1 REAL wdsize : 8 INTEGER wdsize : 4 Beginning session: /home/kamal/neksamples/mine/box.rea timer accuracy: 0.0000000E+00 sec read .rea file nelgt/nelgv/lelt: 15 15 15 lx1 /lx2 /lx3 : 8 6 8 mapping elements to processors 0 15 15 15 15 NELV RANK 0 IEG 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 element load imbalance: 0 15 15 done :: mapping elements to processors 0 objects found done :: read .rea file 0.67091E-03 sec Reset the target Courant number to .5 setup mesh topology Right-handed check complete for 15 elements. OK. setvert2d: 8 252 792 252 252 call usrsetvert done :: usrsetvert gs_setup: 0 unique labels shared handle bytes (avg, min, max): 3972 3972 3972 buffer bytes (avg, min, max): 0 0 0 setupds time 1.9503E-04 seconds 0 8 252 15 4 max multiplicity done :: setup mesh topology call usrdat done :: usrdat generate geometry data vol_t,vol_v: 1.9999999999999920 1.9999999999999920 done :: generate geometry data call usrdat2 done :: usrdat2 regenerate geometry data 1 vol_t,vol_v: 1.9999999999999938 1.9999999999999938 done :: regenerate geometry data 1 verify mesh topology 0.0000000000000000 4.0000000000000000 Xrange 0.0000000000000000 0.50000000000000000 Yrange 0.0000000000000000 0.0000000000000000 Zrange done :: verify mesh topology 103 Parameters from file:/home/kamal/neksamples/mine/box.rea 1 1.00000 p1 DENSITY 2 -20.0000 p2 VISCOS 7 1.00000 p7 RHOCP 8 1.00000 p8 CONDUCT 11 1000.0 p11 NSTEPS 12 -1.000000E-04 p12 DT 15 100.000 p15 IOSTEP 18 0.250000E-01 p18 GRID 19 -1.00000 p19 INTYPE 20 12.0000 p20 NORDER 21 0.100000E-10 p21 DIVERGENCE 22 0.100000E-11 p22 HELMHOLTZ 24 0.100000E-09 p24 TOLREL 25 0.100000E-09 p25 TOLABS 26 1.00000 p26 COURANT/NTAU 27 3.00000 p27 TORDER 28 0. p28 TORDER: mesh velocity (0: p28=p27) 43 1.00000 p43 0=semg/1=schwarz 66 4.00000 p66 output : <0=ascii, else binary 67 4.00000 p67 restart: <0=ascii, else binary 93 20.0000 p93 Number of previous pressure solns saved 94 5.00000 p94 start projecting velocity after p94 step 95 5.00000 p95 start projecting pressure after p95 step 96 1.00000 p96 u0 translational velocity (in .usr) 97 0.30000 p97 v0 translational velocity (in .usr) 99 3.00000 p99 dealiasing: <0--> off/3--> old/4--> new 102 1.00000 p102 Dump out divergence at each time step IFTRAN = T IFFLOW = T IFHEAT = F IFSPLIT = F IFLOMACH = F IFUSERVP = F IFUSERMV = F IFSTRS = F IFCHAR = F IFCYCLIC = F IFAXIS = F IFMVBD = F IFMELT = F IFMODEL = F IFKEPS = F IFMOAB = F IFNEKNEK = F IFSYNC = T IFVCOR = T IFINTQ = F IFCWUZ = F IFSWALL = F IFGEOM = F IFSURT = F IFWCNO = F IFTMSH for field 1 = F IFADVC for field 1 = T IFNONL for field 1 = F Dealiasing enabled, lxd= 12 Estimated eigenvalues EIGAA = 20.047633939712757 EIGGA = 46987.971345031350 EIGAE = 0.61685027506808487 EIGAS = 3.8461538461538464E-003 EIGGE = 46987.971345031350 EIGGS = 2.0000000000000000 verify mesh topology 0.0000000000000000 4.0000000000000000 Xrange 0.0000000000000000 0.50000000000000000 Yrange 0.0000000000000000 0.0000000000000000 Zrange done :: verify mesh topology E-solver strategy: 1 itr 0 15 BC FAIL EXIT: E INVALID BC FOUND in genfast 15 call exitt: dying ... backtrace(): obtained 9 stack frames. ./nek5000(print_stack_+0x1a) [0x4fe90a] ./nek5000(exitt_+0x20f) [0x5bc0af] ./nek5000(exitti_+0x12a) [0x5be72a] ./nek5000(gen_fast_+0x581) [0x4fa701] ./nek5000(set_overlap_+0x125) [0x4eb465] ./nek5000(nek_init_+0x82d) [0x41affd] ./nek5000(main+0x24) [0x419e54] /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf5) [0x7fd9f1f33de5] ./nek5000() [0x419e99] total elapsed time : 3.74889E-03 sec total solver time incl. I/O : 0.00000E+00 sec time/timestep : 0.00000E+00 sec CPU seconds/timestep/gridpt : 0.00000E+00 sec real 0m0.030s user 0m0.020s sys 0m0.000s -------------- next part -------------- 15 24 3 8 60 24 0 7 8 7 19 18 7 7 16 18 17 6 16 24 17 23 3 24 6 23 11 3 6 5 11 10 5 19 18 15 14 5 18 17 14 22 6 17 23 22 21 2 23 11 21 13 2 11 10 13 12 4 15 14 4 3 4 14 22 3 20 1 22 21 20 2 1 21 13 2 9 0 13 12 9 1 -------------- next part -------------- ****** PARAMETERS ***** 2.610000 NEKTON VERSION 2 DIMENSIONAL RUN 103 PARAMETERS FOLLOW 1.00000 p1 DENSITY -20.0000 p2 VISCOS 0. 0. 0. 0. 1.00000 p7 RHOCP 1.00000 p8 CONDUCT 0. 0. p10 FINTIME 1000.0 p11 NSTEPS -1.000000E-04 p12 DT 0. p13 IOCOMM 0. p14 IOTIME 100.000 p15 IOSTEP 0. p16 PSSOLVER 0. 0.250000E-01 p18 GRID -1.00000 p19 INTYPE 12.0000 p20 NORDER 0.100000E-10 p21 DIVERGENCE 0.100000E-11 p22 HELMHOLTZ 0 p23 NPSCAL 0.100000E-09 p24 TOLREL 0.100000E-09 p25 TOLABS 1.00000 p26 COURANT/NTAU 3.00000 p27 TORDER 0. p28 TORDER: mesh velocity (0: p28=p27) 0. p29 magnetic visc if > 0, = -1/Rm if < 0 0. p30 > 0 ==> properties set in uservp() 0. p31 NPERT: #perturbation modes 0. p32 #BCs in re2 file, if > 0 0. 0. 0. 0. 0. 0. 0. 0. 0. p41 1-->multiplicative SEMG 0. p42 0=gmres/1=pcg 1.00000 p43 0=semg/1=schwarz 0. p44 0=E-based/1=A-based prec. 0. p45 Relaxation factor for DTFS 0. p46 reserved 0. p47 vnu: mesh matieral prop 0. 0. 0. 0. 0. p52 IOHIS 0. 0. p54 1,2,3-->fixed flow rate dir=x,y,z 0. p55 vol.flow rate (p54>0) or Ubar (p54<0) 0. 0. 0. 0. p59 !=0 --> full Jac. eval. for each el. 0. p60 !=0 --> init. velocity to small nonzero 0. 0. p62 >0 --> force byte_swap for output 0. p63 =8 --> force 8-byte output 0. p64 =1 --> perturbation restart 0. p65 #iofiles (eg, 0 or 64); <0 --> sep. dirs 4.00000 p66 output : <0=ascii, else binary 4.00000 p67 restart: <0=ascii, else binary 0. p68 iastep: freq for avg_all 0. 0. 0. 0. 0. 0. p74 verbose Helmholtz 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. p84 !=0 --> sets initial timestep if p12>0 0. p85 dt ratio if p84 !=0, for timesteps>0 0. p86 reserved 0. 0. 0. 0. 0. 0. 20.0000 p93 Number of previous pressure solns saved 5.00000 p94 start projecting velocity after p94 step 5.00000 p95 start projecting pressure after p95 step 1.00000 p96 u0 translational velocity (in .usr) 0.30000 p97 v0 translational velocity (in .usr) 0. 3.00000 p99 dealiasing: <0--> off/3--> old/4--> new 0. 0. p101 No. of additional filter modes 1.00000 p102 Dump out divergence at each time step .000 p103 weight of stabilizing filter (.01) 4 Lines of passive scalar data follows2 CONDUCT; 2RHOCP 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 13 LOGICAL SWITCHES FOLLOW T IFFLOW F IFHEAT T IFTRAN T F F F F F F F F F F IFNAV & IFADVC (convection in P.S. fields) F F T T T T T T T T T T IFTMSH (IF mesh for this field is T mesh) F IFAXIS F IFSTRS F IFSPLIT F IFMGRID F IFMODEL F IFKEPS F IFMVBD F IFCHAR 4.00000 0.50000 0.00 0.00 XFAC,YFAC,XZERO,YZERO **MESH DATA** 6 lines are X,Y,Z;X,Y,Z. Columns corners 1-4;5-8 15 2 15 NEL,NDIM,NELV ELEMENT 1 [ 1a] GROUP 0 0.00000 0.800000 0.800000 0.00000 0.00000 0.00000 0.166667 0.166667 ELEMENT 2 [ 1b] GROUP 0 0.800000 1.60000 1.60000 0.800000 0.00000 0.00000 0.166667 0.166667 ELEMENT 3 [ 1c] GROUP 0 1.60000 2.40000 2.40000 1.60000 0.00000 0.00000 0.166667 0.166667 ELEMENT 4 [ 1d] GROUP 0 2.40000 3.20000 3.20000 2.40000 0.00000 0.00000 0.166667 0.166667 ELEMENT 5 [ 1e] GROUP 0 3.20000 4.00000 4.00000 3.20000 0.00000 0.00000 0.166667 0.166667 ELEMENT 6 [ 1f] GROUP 0 0.00000 0.800000 0.800000 0.00000 0.166667 0.166667 0.333333 0.333333 ELEMENT 7 [ 1g] GROUP 0 0.800000 1.60000 1.60000 0.800000 0.166667 0.166667 0.333333 0.333333 ELEMENT 8 [ 1h] GROUP 0 1.60000 2.40000 2.40000 1.60000 0.166667 0.166667 0.333333 0.333333 ELEMENT 9 [ 1i] GROUP 0 2.40000 3.20000 3.20000 2.40000 0.166667 0.166667 0.333333 0.333333 ELEMENT 10 [ 1j] GROUP 0 3.20000 4.00000 4.00000 3.20000 0.166667 0.166667 0.333333 0.333333 ELEMENT 11 [ 1k] GROUP 0 0.00000 0.800000 0.800000 0.00000 0.333333 0.333333 0.500000 0.500000 ELEMENT 12 [ 1l] GROUP 0 0.800000 1.60000 1.60000 0.800000 0.333333 0.333333 0.500000 0.500000 ELEMENT 13 [ 1m] GROUP 0 1.60000 2.40000 2.40000 1.60000 0.333333 0.333333 0.500000 0.500000 ELEMENT 14 [ 1n] GROUP 0 2.40000 3.20000 3.20000 2.40000 0.333333 0.333333 0.500000 0.500000 ELEMENT 15 [ 1o] GROUP 0 3.20000 4.00000 4.00000 3.20000 0.333333 0.333333 0.500000 0.500000 ***** CURVED SIDE DATA ***** 0 Curved sides follow IEDGE,IEL,CURVE(I),I=1,5, CCURVE ***** BOUNDARY CONDITIONS ***** ***** FLUID BOUNDARY CONDITIONS ***** ,W 1 1 0.00000 0.00000 0.00000 0.00000 0.00000 E 1 2 2.00000 4.00000 0.00000 0.00000 0.00000 E 1 3 6.00000 1.00000 0.00000 0.00000 0.00000 v , 1 4 0.00000 0.00000 0.00000 0.00000 0.00000 ,W 2 1 0.00000 0.00000 0.00000 0.00000 0.00000 E 2 2 3.00000 4.00000 0.00000 0.00000 0.00000 E 2 3 7.00000 1.00000 0.00000 0.00000 0.00000 E 2 4 1.00000 2.00000 0.00000 0.00000 0.00000 ,W 3 1 0.00000 0.00000 0.00000 0.00000 0.00000 E 3 2 4.00000 4.00000 0.00000 0.00000 0.00000 E 3 3 8.00000 1.00000 0.00000 0.00000 0.00000 E 3 4 2.00000 2.00000 0.00000 0.00000 0.00000 ,W 4 1 0.00000 0.00000 0.00000 0.00000 0.00000 E 4 2 5.00000 4.00000 0.00000 0.00000 0.00000 E 4 3 9.00000 1.00000 0.00000 0.00000 0.00000 E 4 4 3.00000 2.00000 0.00000 0.00000 0.00000 ,W 5 1 0.00000 0.00000 0.00000 0.00000 0.00000 ,A 5 2 0.00000 0.00000 0.00000 0.00000 0.00000 E 5 3 10.0000 1.00000 0.00000 0.00000 0.00000 E 5 4 4.00000 2.00000 0.00000 0.00000 0.00000 E 6 1 1.00000 3.00000 0.00000 0.00000 0.00000 E 6 2 7.00000 4.00000 0.00000 0.00000 0.00000 E 6 3 11.0000 1.00000 0.00000 0.00000 0.00000 v , 6 4 0.00000 0.00000 0.00000 0.00000 0.00000 E 7 1 2.00000 3.00000 0.00000 0.00000 0.00000 E 7 2 8.00000 4.00000 0.00000 0.00000 0.00000 E 7 3 12.0000 1.00000 0.00000 0.00000 0.00000 E 7 4 6.00000 2.00000 0.00000 0.00000 0.00000 E 8 1 3.00000 3.00000 0.00000 0.00000 0.00000 E 8 2 9.00000 4.00000 0.00000 0.00000 0.00000 E 8 3 13.0000 1.00000 0.00000 0.00000 0.00000 E 8 4 7.00000 2.00000 0.00000 0.00000 0.00000 E 9 1 4.00000 3.00000 0.00000 0.00000 0.00000 E 9 2 10.0000 4.00000 0.00000 0.00000 0.00000 E 9 3 14.0000 1.00000 0.00000 0.00000 0.00000 E 9 4 8.00000 2.00000 0.00000 0.00000 0.00000 E 10 1 5.00000 3.00000 0.00000 0.00000 0.00000 ,A 10 2 0.00000 0.00000 0.00000 0.00000 0.00000 E 10 3 15.0000 1.00000 0.00000 0.00000 0.00000 E 10 4 9.00000 2.00000 0.00000 0.00000 0.00000 E 11 1 6.00000 3.00000 0.00000 0.00000 0.00000 E 11 2 12.0000 4.00000 0.00000 0.00000 0.00000 , 11 3 0.00000 0.00000 0.00000 0.00000 0.00000 v , 11 4 0.00000 0.00000 0.00000 0.00000 0.00000 E 12 1 7.00000 3.00000 0.00000 0.00000 0.00000 E 12 2 13.0000 4.00000 0.00000 0.00000 0.00000 , 12 3 0.00000 0.00000 0.00000 0.00000 0.00000 E 12 4 11.0000 2.00000 0.00000 0.00000 0.00000 E 13 1 8.00000 3.00000 0.00000 0.00000 0.00000 E 13 2 14.0000 4.00000 0.00000 0.00000 0.00000 , 13 3 0.00000 0.00000 0.00000 0.00000 0.00000 E 13 4 12.0000 2.00000 0.00000 0.00000 0.00000 E 14 1 9.00000 3.00000 0.00000 0.00000 0.00000 E 14 2 15.0000 4.00000 0.00000 0.00000 0.00000 , 14 3 0.00000 0.00000 0.00000 0.00000 0.00000 E 14 4 13.0000 2.00000 0.00000 0.00000 0.00000 E 15 1 10.0000 3.00000 0.00000 0.00000 0.00000 ,A 15 2 0.00000 0.00000 0.00000 0.00000 0.00000 , 15 3 0.00000 0.00000 0.00000 0.00000 0.00000 E 15 4 14.0000 2.00000 0.00000 0.00000 0.00000 ***** NO THERMAL BOUNDARY CONDITIONS ***** 0 PRESOLVE/RESTART OPTIONS ***** 7 INITIAL CONDITIONS ***** C Default C Default C Default C Default C Default C Default C Default ***** DRIVE FORCE DATA ***** BODY FORCE, FLOW, Q 4 Lines of Drive force data follow C C C C ***** Variable Property Data ***** Overrrides Parameter data. 1 Lines follow. 0 PACKETS OF DATA FOLLOW ***** HISTORY AND INTEGRAL DATA ***** 0 POINTS. Hcode, I,J,H,IEL ***** OUTPUT FIELD SPECIFICATION ***** 6 SPECIFICATIONS FOLLOW T COORDINATES T VELOCITY T PRESSURE F TEMPERATURE F TEMPERATURE GRADIENT 0 PASSIVE SCALARS ***** OBJECT SPECIFICATION ***** 0 Surface Objects 0 Volume Objects 0 Edge Objects 0 Point Objects -------------- next part -------------- c----------------------------------------------------------------------- subroutine uservp (ix,iy,iz,ieg) include 'SIZE' include 'TOTAL' include 'NEKUSE' C udiff =0. utrans=0. return end c----------------------------------------------------------------------- subroutine userf (ix,iy,iz,ieg) include 'SIZE' include 'TOTAL' include 'NEKUSE' c ffx = 0.0 ffy = 0.0 ffz = 0.0 return end c----------------------------------------------------------------------- subroutine userq (ix,iy,iz,ieg) include 'SIZE' include 'TOTAL' include 'NEKUSE' C qvol = 0.0 source = 0.0 return end c----------------------------------------------------------------------- subroutine userchk ! called once per step include 'SIZE' include 'TOTAL' c n = nx1*ny1*nz1*nelv visc = param(2) u0 = param(96) v0 = param(97) if (istep.eq.0 ) call outpost(ue,ve,vx,pr,t,' ') call sub3 (ud,ue,vx,n) call sub3 (vd,ve,vy,n) if (istep.eq.nsteps) call outpost(ud,vd,vx,pr,t,' ') umx = glamax(vx,n) vmx = glamax(vy,n) uex = glamax(ue,n) vex = glamax(ve,n) udx = glamax(ud,n) vdx = glamax(vd,n) if (nid.eq.0) then write(6,11) istep,time,udx,umx,uex,u0,' X err' write(6,11) istep,time,vdx,vmx,vex,v0,' Y err' 11 format(i5,1p5e14.6,a7) endif if (istep.le.5) then ! Reset velocity to eliminate call copy (vx,ue,n) ! start-up contributions to call copy (vy,ve,n) ! temporal-accuracy behavior. endif return end c----------------------------------------------------------------------- subroutine userbc (ix,iy,iz,iside,ieg) include 'SIZE' include 'TOTAL' include 'NEKUSE' ux = 1.0 uy = 0.0 temp = 0 return end c----------------------------------------------------------------------- subroutine useric (ix,iy,iz,ieg) include 'SIZE' include 'TOTAL' include 'NEKUSE' ux = 1.0 uy = 0.0 temp = 0 return end c----------------------------------------------------------------------- subroutine usrdat return end c----------------------------------------------------------------------- subroutine usrdat2 return end c----------------------------------------------------------------------- subroutine usrdat3 return end c----------------------------------------------------------------------- -------------- next part -------------- C Dimension file to be included C C HCUBE array dimensions C parameter (ldim=2) parameter (lx1=8,ly1=lx1,lz1=1,lelt=15,lelv=lelt) parameter (lxd=12,lyd=lxd,lzd=1) parameter (lelx=20,lely=20,lelz=1) parameter (lzl=3 + 2*(ldim-3)) parameter (lx2=lx1-2) parameter (ly2=ly1-2) parameter (lz2=lz1 ) parameter (lx3=lx1) parameter (ly3=ly1) parameter (lz3=lz1) parameter (lp = 512) parameter (lelg = 4100) c c parameter (lpelv=lelv,lpelt=lelt,lpert=3) ! perturbation c parameter (lpx1=lx1,lpy1=ly1,lpz1=lz1) ! array sizes c parameter (lpx2=lx2,lpy2=ly2,lpz2=lz2) c parameter (lpelv=1,lpelt=1,lpert=1) ! perturbation parameter (lpx1=1,lpy1=1,lpz1=1) ! array sizes parameter (lpx2=1,lpy2=1,lpz2=1) c c parameter (lbelv=lelv,lbelt=lelt) ! MHD c parameter (lbx1=lx1,lby1=ly1,lbz1=lz1) ! array sizes c parameter (lbx2=lx2,lby2=ly2,lbz2=lz2) c parameter (lbelv=1,lbelt=1) ! MHD parameter (lbx1=1,lby1=1,lbz1=1) ! array sizes parameter (lbx2=1,lby2=1,lbz2=1) C LX1M=LX1 when there are moving meshes; =1 otherwise parameter (lx1m=1,ly1m=1,lz1m=1) parameter (ldimt= 2) ! 2 passive scalars + T parameter (ldimt1=ldimt+1) parameter (ldimt3=ldimt+3) c c Note: In the new code, LELGEC should be about sqrt(LELG) c PARAMETER (LELGEC = 1) PARAMETER (LXYZ2 = 1) PARAMETER (LXZ21 = 1) PARAMETER (LMAXV=LX1*LY1*LZ1*LELV) PARAMETER (LMAXT=LX1*LY1*LZ1*LELT) PARAMETER (LMAXP=LX2*LY2*LZ2*LELV) PARAMETER (LXZ=LX1*LZ1) PARAMETER (LORDER=3) PARAMETER (MAXOBJ=4,MAXMBR=LELT*6) PARAMETER (lhis=100) ! # of pts a proc reads from hpts.in ! Note: lhis*np > npoints in hpts.in C C Common Block Dimensions C PARAMETER (LCTMP0 =2*LX1*LY1*LZ1*LELT) PARAMETER (LCTMP1 =4*LX1*LY1*LZ1*LELT) C C The parameter LVEC controls whether an additional 42 field arrays C are required for Steady State Solutions. If you are not using C Steady State, it is recommended that LVEC=1. C PARAMETER (LVEC=1) C C Uzawa projection array dimensions C parameter (mxprev = 20) parameter (lgmres = 30) C C Split projection array dimensions C parameter(lmvec = 1) parameter(lsvec = 1) parameter(lstore=lmvec*lsvec) c c NONCONFORMING STUFF c parameter (maxmor = lelt) C C Array dimensions C COMMON/DIMN/NELV,NELT,NX1,NY1,NZ1,NX2,NY2,NZ2 $,NX3,NY3,NZ3,NDIM,NFIELD,NPERT,NID $,NXD,NYD,NZD c automatically added by makenek parameter(lxo = lx1) ! max output grid size (lxo>=lx1) c automatically added by makenek parameter(lpart = 1 ) ! max number of particles c automatically added by makenek integer ax1,ay1,az1,ax2,ay2,az2 parameter (ax1=lx1,ay1=ly1,az1=lz1,ax2=lx2,ay2=ly2,az2=lz2) ! running averages c automatically added by makenek parameter (lxs=1,lys=lxs,lzs=(lxs-1)*(ldim-2)+1) !New Pressure Preconditioner c automatically added by makenek parameter (lfdm=0) ! == 1 for fast diagonalization method -------------- next part -------------- ****** PARAMETERS ***** 2.610000 NEKTON VERSION 2 DIMENSIONAL RUN 103 PARAMETERS FOLLOW 1.00000 p1 DENSITY -20.0000 p2 VISCOS 0. 0. 0. 0. 1.00000 p7 RHOCP 1.00000 p8 CONDUCT 0. 0. p10 FINTIME 1000.0 p11 NSTEPS -1.000000E-04 p12 DT 0. p13 IOCOMM 0. p14 IOTIME 100.000 p15 IOSTEP 0. p16 PSSOLVER 0. 0.250000E-01 p18 GRID -1.00000 p19 INTYPE 12.0000 p20 NORDER 0.100000E-10 p21 DIVERGENCE 0.100000E-11 p22 HELMHOLTZ 0. p23 NPSCAL 0.100000E-09 p24 TOLREL 0.100000E-09 p25 TOLABS 1.00000 p26 COURANT/NTAU 3.00000 p27 TORDER 0. p28 TORDER: mesh velocity (0: p28=p27) 0. p29 magnetic visc if > 0, = -1/Rm if < 0 0. p30 > 0 ==> properties set in uservp() 0. p31 NPERT: #perturbation modes 0. p32 #BCs in re2 file, if > 0 0. 0. 0. 0. 0. 0. 0. 0. 0. p41 1-->multiplicative SEMG 0. p42 0=gmres/1=pcg 1.00000 p43 0=semg/1=schwarz 0. p44 0=E-based/1=A-based prec. 0. p45 Relaxation factor for DTFS 0. p46 reserved 0. p47 vnu: mesh matieral prop 0. 0. 0. 0. 0. p52 IOHIS 0. 0. p54 1,2,3-->fixed flow rate dir=x,y,z 0. p55 vol.flow rate (p54>0) or Ubar (p54<0) 0. 0. 0. 0. p59 !=0 --> full Jac. eval. for each el. 0. p60 !=0 --> init. velocity to small nonzero 0. 0. p62 >0 --> force byte_swap for output 0. p63 =8 --> force 8-byte output 0. p64 =1 --> perturbation restart 0. p65 #iofiles (eg, 0 or 64); <0 --> sep. dirs 4.00000 p66 output : <0=ascii, else binary 4.00000 p67 restart: <0=ascii, else binary 0. p68 iastep: freq for avg_all 0. 0. 0. 0. 0. 0. p74 verbose Helmholtz 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. p84 !=0 --> sets initial timestep if p12>0 0. p85 dt ratio if p84 !=0, for timesteps>0 0. p86 reserved 0. 0. 0. 0. 0. 0. 20.0000 p93 Number of previous pressure solns saved 5.00000 p94 start projecting velocity after p94 step 5.00000 p95 start projecting pressure after p95 step 1.00000 p96 u0 translational velocity (in .usr) 0.30000 p97 v0 translational velocity (in .usr) 0. 3.00000 p99 dealiasing: <0--> off/3--> old/4--> new 0. 0. p101 No. of additional filter modes 1.00000 p102 Dump out divergence at each time step .000 p103 weight of stabilizing filter (.01) 4 Lines of passive scalar data follows2 CONDUCT; 2RHOCP 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 1.00000 13 LOGICAL SWITCHES FOLLOW T IFFLOW F IFHEAT T IFTRAN T F F F F F F F F F F IFNAV & IFADVC (convection in P.S. fields) F F T T T T T T T T T T IFTMSH (IF mesh for this field is T mesh) F IFAXIS F IFSTRS F IFSPLIT F IFMGRID F IFMODEL F IFKEPS F IFMVBD F IFCHAR From nek5000-users at lists.mcs.anl.gov Mon Jan 13 12:58:18 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Mon, 13 Jan 2014 12:58:18 -0600 Subject: [Nek5000-users] Problem in 2d pipe simulation In-Reply-To: References: Message-ID: Hi, When you create the .box file, it is important that the line containing the boundary conditions follows the format as described on the nek wiki and documentation. It is a 3 character code that defines each boundary condition, and the whitespace must be maintained. For example, "v ,A ,W ,W , , " would be a valid entry, whereas using less than 3 characters will result in commas and whitespace being entered into your .rea file. More info and examples can be found: http://nek5000.mcs.anl.gov/index.php/Genbox Best, Katie On Mon, Jan 13, 2014 at 8:49 AM, wrote: > Hi, > > I created my .box file, with help of genbox I created .rea file. > later I created a .usr and SIZE file. > > I have attached all the files I used with this mail > > I launched the simulation and I got this error > > ***************************************************************** > /----------------------------------------------------------\\ > | _ __ ______ __ __ ______ ____ ____ ____ | > | / | / // ____// //_/ / ____/ / __ \\ / __ \\ / __ \\ | > | / |/ // __/ / ,< /___ \\ / / / // / / // / / / | > | / /| // /___ / /| | ____/ / / /_/ // /_/ // /_/ / | > | /_/ |_//_____//_/ |_|/_____/ \\____/ \\____/ \\____/ | > | | > |----------------------------------------------------------| > | | > | NEK5000: Open Source Spectral Element Solver | > | COPYRIGHT (c) 2008-2010 UCHICAGO ARGONNE, LLC | > | Version: 1.0rc1 / SVN r982 | > | Web: http://nek5000.mcs.anl.gov | > | | > \\----------------------------------------------------------/ > > > Number of processors: 1 > REAL wdsize : 8 > INTEGER wdsize : 4 > > > Beginning session: > /home/kamal/neksamples/mine/box.rea > > > timer accuracy: 0.0000000E+00 sec > > read .rea file > nelgt/nelgv/lelt: 15 15 15 > lx1 /lx2 /lx3 : 8 6 8 > > mapping elements to processors > 0 15 15 15 15 NELV > RANK 0 IEG 1 2 3 4 5 6 7 8 > 9 10 11 12 13 14 15 > element load imbalance: 0 15 15 > done :: mapping elements to processors > > 0 objects found > done :: read .rea file 0.67091E-03 sec > > Reset the target Courant number to .5 > setup mesh topology > Right-handed check complete for 15 elements. OK. > setvert2d: 8 252 792 252 252 > call usrsetvert > done :: usrsetvert > > gs_setup: 0 unique labels shared > handle bytes (avg, min, max): 3972 3972 3972 > buffer bytes (avg, min, max): 0 0 0 > setupds time 1.9503E-04 seconds 0 8 252 15 > 4 max multiplicity > done :: setup mesh topology > > call usrdat > done :: usrdat > > generate geometry data > vol_t,vol_v: 1.9999999999999920 1.9999999999999920 > done :: generate geometry data > > call usrdat2 > done :: usrdat2 > > regenerate geometry data 1 > vol_t,vol_v: 1.9999999999999938 1.9999999999999938 > done :: regenerate geometry data 1 > > verify mesh topology > 0.0000000000000000 4.0000000000000000 Xrange > 0.0000000000000000 0.50000000000000000 Yrange > 0.0000000000000000 0.0000000000000000 Zrange > done :: verify mesh topology > > 103 Parameters from file:/home/kamal/neksamples/mine/box.rea > 1 1.00000 p1 DENSITY > 2 -20.0000 p2 VISCOS > 7 1.00000 p7 RHOCP > 8 1.00000 p8 CONDUCT > 11 1000.0 p11 NSTEPS > 12 -1.000000E-04 p12 DT > 15 100.000 p15 IOSTEP > 18 0.250000E-01 p18 GRID > 19 -1.00000 p19 INTYPE > 20 12.0000 p20 NORDER > 21 0.100000E-10 p21 DIVERGENCE > 22 0.100000E-11 p22 HELMHOLTZ > 24 0.100000E-09 p24 TOLREL > 25 0.100000E-09 p25 TOLABS > 26 1.00000 p26 COURANT/NTAU > 27 3.00000 p27 TORDER > 28 0. p28 TORDER: mesh velocity (0: p28=p27) > 43 1.00000 p43 0=semg/1=schwarz > 66 4.00000 p66 output : <0=ascii, else binary > 67 4.00000 p67 restart: <0=ascii, else binary > 93 20.0000 p93 Number of previous pressure solns saved > 94 5.00000 p94 start projecting velocity after p94 step > 95 5.00000 p95 start projecting pressure after p95 step > 96 1.00000 p96 u0 translational velocity (in .usr) > 97 0.30000 p97 v0 translational velocity (in .usr) > 99 3.00000 p99 dealiasing: <0--> off/3--> old/4--> new > 102 1.00000 p102 Dump out divergence at each time step > > IFTRAN = T > IFFLOW = T > IFHEAT = F > IFSPLIT = F > IFLOMACH = F > IFUSERVP = F > IFUSERMV = F > IFSTRS = F > IFCHAR = F > IFCYCLIC = F > IFAXIS = F > IFMVBD = F > IFMELT = F > IFMODEL = F > IFKEPS = F > IFMOAB = F > IFNEKNEK = F > IFSYNC = T > > IFVCOR = T > IFINTQ = F > IFCWUZ = F > IFSWALL = F > IFGEOM = F > IFSURT = F > IFWCNO = F > > IFTMSH for field 1 = F > IFADVC for field 1 = T > IFNONL for field 1 = F > > Dealiasing enabled, lxd= 12 > > Estimated eigenvalues > EIGAA = 20.047633939712757 > EIGGA = 46987.971345031350 > EIGAE = 0.61685027506808487 > EIGAS = 3.8461538461538464E-003 > EIGGE = 46987.971345031350 > EIGGS = 2.0000000000000000 > > verify mesh topology > 0.0000000000000000 4.0000000000000000 Xrange > 0.0000000000000000 0.50000000000000000 Yrange > 0.0000000000000000 0.0000000000000000 Zrange > done :: verify mesh topology > > E-solver strategy: 1 itr > 0 15 BC FAIL > EXIT: E INVALID BC FOUND in genfast 15 > > call exitt: dying ... > > backtrace(): obtained 9 stack frames. > ./nek5000(print_stack_+0x1a) [0x4fe90a] > ./nek5000(exitt_+0x20f) [0x5bc0af] > ./nek5000(exitti_+0x12a) [0x5be72a] > ./nek5000(gen_fast_+0x581) [0x4fa701] > ./nek5000(set_overlap_+0x125) [0x4eb465] > ./nek5000(nek_init_+0x82d) [0x41affd] > ./nek5000(main+0x24) [0x419e54] > /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf5) [0x7fd9f1f33de5] > ./nek5000() [0x419e99] > > total elapsed time : 3.74889E-03 sec > total solver time incl. I/O : 0.00000E+00 sec > time/timestep : 0.00000E+00 sec > CPU seconds/timestep/gridpt : 0.00000E+00 sec > > > real 0m0.030s > user 0m0.020s > sys 0m0.000s > > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Mon Jan 13 13:03:54 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Mon, 13 Jan 2014 20:03:54 +0100 Subject: [Nek5000-users] Problem in 2d pipe simulation In-Reply-To: References: Message-ID: Thanks a lot. Could you please tell me where I can find more information of defining the .usr file. for example if I have boundary condition like this on a pipe " v,O,W,W " and If I want to define a parabolic profile on the inlet say a value of 10 . How do I specific the edge ? Thank you. Kamal On Jan 13, 2014, at 7:58 PM, nek5000-users at lists.mcs.anl.gov wrote: > Hi, > > When you create the .box file, it is important that the line containing the boundary conditions follows the format as described on the nek wiki and documentation. > > It is a 3 character code that defines each boundary condition, and the whitespace must be maintained. For example, > > "v ,A ,W ,W , , " > > would be a valid entry, whereas using less than 3 characters will result in commas and whitespace being entered into your .rea file. > > More info and examples can be found: > http://nek5000.mcs.anl.gov/index.php/Genbox > > Best, > Katie > > > On Mon, Jan 13, 2014 at 8:49 AM, wrote: > Hi, > > I created my .box file, with help of genbox I created .rea file. > later I created a .usr and SIZE file. > > I have attached all the files I used with this mail > > I launched the simulation and I got this error > > ***************************************************************** > /----------------------------------------------------------\\ > | _ __ ______ __ __ ______ ____ ____ ____ | > | / | / // ____// //_/ / ____/ / __ \\ / __ \\ / __ \\ | > | / |/ // __/ / ,< /___ \\ / / / // / / // / / / | > | / /| // /___ / /| | ____/ / / /_/ // /_/ // /_/ / | > | /_/ |_//_____//_/ |_|/_____/ \\____/ \\____/ \\____/ | > | | > |----------------------------------------------------------| > | | > | NEK5000: Open Source Spectral Element Solver | > | COPYRIGHT (c) 2008-2010 UCHICAGO ARGONNE, LLC | > | Version: 1.0rc1 / SVN r982 | > | Web: http://nek5000.mcs.anl.gov | > | | > \\----------------------------------------------------------/ > > > Number of processors: 1 > REAL wdsize : 8 > INTEGER wdsize : 4 > > > Beginning session: > /home/kamal/neksamples/mine/box.rea > > > timer accuracy: 0.0000000E+00 sec > > read .rea file > nelgt/nelgv/lelt: 15 15 15 > lx1 /lx2 /lx3 : 8 6 8 > > mapping elements to processors > 0 15 15 15 15 NELV > RANK 0 IEG 1 2 3 4 5 6 7 8 > 9 10 11 12 13 14 15 > element load imbalance: 0 15 15 > done :: mapping elements to processors > > 0 objects found > done :: read .rea file 0.67091E-03 sec > > Reset the target Courant number to .5 > setup mesh topology > Right-handed check complete for 15 elements. OK. > setvert2d: 8 252 792 252 252 > call usrsetvert > done :: usrsetvert > > gs_setup: 0 unique labels shared > handle bytes (avg, min, max): 3972 3972 3972 > buffer bytes (avg, min, max): 0 0 0 > setupds time 1.9503E-04 seconds 0 8 252 15 > 4 max multiplicity > done :: setup mesh topology > > call usrdat > done :: usrdat > > generate geometry data > vol_t,vol_v: 1.9999999999999920 1.9999999999999920 > done :: generate geometry data > > call usrdat2 > done :: usrdat2 > > regenerate geometry data 1 > vol_t,vol_v: 1.9999999999999938 1.9999999999999938 > done :: regenerate geometry data 1 > > verify mesh topology > 0.0000000000000000 4.0000000000000000 Xrange > 0.0000000000000000 0.50000000000000000 Yrange > 0.0000000000000000 0.0000000000000000 Zrange > done :: verify mesh topology > > 103 Parameters from file:/home/kamal/neksamples/mine/box.rea > 1 1.00000 p1 DENSITY > 2 -20.0000 p2 VISCOS > 7 1.00000 p7 RHOCP > 8 1.00000 p8 CONDUCT > 11 1000.0 p11 NSTEPS > 12 -1.000000E-04 p12 DT > 15 100.000 p15 IOSTEP > 18 0.250000E-01 p18 GRID > 19 -1.00000 p19 INTYPE > 20 12.0000 p20 NORDER > 21 0.100000E-10 p21 DIVERGENCE > 22 0.100000E-11 p22 HELMHOLTZ > 24 0.100000E-09 p24 TOLREL > 25 0.100000E-09 p25 TOLABS > 26 1.00000 p26 COURANT/NTAU > 27 3.00000 p27 TORDER > 28 0. p28 TORDER: mesh velocity (0: p28=p27) > 43 1.00000 p43 0=semg/1=schwarz > 66 4.00000 p66 output : <0=ascii, else binary > 67 4.00000 p67 restart: <0=ascii, else binary > 93 20.0000 p93 Number of previous pressure solns saved > 94 5.00000 p94 start projecting velocity after p94 step > 95 5.00000 p95 start projecting pressure after p95 step > 96 1.00000 p96 u0 translational velocity (in .usr) > 97 0.30000 p97 v0 translational velocity (in .usr) > 99 3.00000 p99 dealiasing: <0--> off/3--> old/4--> new > 102 1.00000 p102 Dump out divergence at each time step > > IFTRAN = T > IFFLOW = T > IFHEAT = F > IFSPLIT = F > IFLOMACH = F > IFUSERVP = F > IFUSERMV = F > IFSTRS = F > IFCHAR = F > IFCYCLIC = F > IFAXIS = F > IFMVBD = F > IFMELT = F > IFMODEL = F > IFKEPS = F > IFMOAB = F > IFNEKNEK = F > IFSYNC = T > > IFVCOR = T > IFINTQ = F > IFCWUZ = F > IFSWALL = F > IFGEOM = F > IFSURT = F > IFWCNO = F > > IFTMSH for field 1 = F > IFADVC for field 1 = T > IFNONL for field 1 = F > > Dealiasing enabled, lxd= 12 > > Estimated eigenvalues > EIGAA = 20.047633939712757 > EIGGA = 46987.971345031350 > EIGAE = 0.61685027506808487 > EIGAS = 3.8461538461538464E-003 > EIGGE = 46987.971345031350 > EIGGS = 2.0000000000000000 > > verify mesh topology > 0.0000000000000000 4.0000000000000000 Xrange > 0.0000000000000000 0.50000000000000000 Yrange > 0.0000000000000000 0.0000000000000000 Zrange > done :: verify mesh topology > > E-solver strategy: 1 itr > 0 15 BC FAIL > EXIT: E INVALID BC FOUND in genfast 15 > > call exitt: dying ... > > backtrace(): obtained 9 stack frames. > ./nek5000(print_stack_+0x1a) [0x4fe90a] > ./nek5000(exitt_+0x20f) [0x5bc0af] > ./nek5000(exitti_+0x12a) [0x5be72a] > ./nek5000(gen_fast_+0x581) [0x4fa701] > ./nek5000(set_overlap_+0x125) [0x4eb465] > ./nek5000(nek_init_+0x82d) [0x41affd] > ./nek5000(main+0x24) [0x419e54] > /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf5) [0x7fd9f1f33de5] > ./nek5000() [0x419e99] > > total elapsed time : 3.74889E-03 sec > total solver time incl. I/O : 0.00000E+00 sec > time/timestep : 0.00000E+00 sec > CPU seconds/timestep/gridpt : 0.00000E+00 sec > > > real 0m0.030s > user 0m0.020s > sys 0m0.000s > > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Mon Jan 13 13:30:29 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Mon, 13 Jan 2014 13:30:29 -0600 (CST) Subject: [Nek5000-users] Problem in 2d pipe simulation In-Reply-To: References: Message-ID: Hi Kamal, Go to https://nek5000.mcs.anl.gov/index.php/UG#Documentation and click on the Nek5000 manual. On pg. 35 there are examples of how to specify functions. Several of the cases in /examples also have prescribed functions for boundary conditions --- for example, the Kovasznay case. Best, Paul On Mon, 13 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > Thanks a lot. > > Could you please tell me where I can find more information of defining the .usr file. > > for example if I have boundary condition like this on a pipe > > " v,O,W,W " > > and If I want to define a parabolic profile on the inlet say a value of 10 . How do I specific the edge ? > > Thank you. > > Kamal > > On Jan 13, 2014, at 7:58 PM, nek5000-users at lists.mcs.anl.gov wrote: > >> Hi, >> >> When you create the .box file, it is important that the line containing the boundary conditions follows the format as described on the nek wiki and documentation. >> >> It is a 3 character code that defines each boundary condition, and the whitespace must be maintained. For example, >> >> "v ,A ,W ,W , , " >> >> would be a valid entry, whereas using less than 3 characters will result in commas and whitespace being entered into your .rea file. >> >> More info and examples can be found: >> http://nek5000.mcs.anl.gov/index.php/Genbox >> >> Best, >> Katie >> >> >> On Mon, Jan 13, 2014 at 8:49 AM, wrote: >> Hi, >> >> I created my .box file, with help of genbox I created .rea file. >> later I created a .usr and SIZE file. >> >> I have attached all the files I used with this mail >> >> I launched the simulation and I got this error >> >> ***************************************************************** >> /----------------------------------------------------------\\ >> | _ __ ______ __ __ ______ ____ ____ ____ | >> | / | / // ____// //_/ / ____/ / __ \\ / __ \\ / __ \\ | >> | / |/ // __/ / ,< /___ \\ / / / // / / // / / / | >> | / /| // /___ / /| | ____/ / / /_/ // /_/ // /_/ / | >> | /_/ |_//_____//_/ |_|/_____/ \\____/ \\____/ \\____/ | >> | | >> |----------------------------------------------------------| >> | | >> | NEK5000: Open Source Spectral Element Solver | >> | COPYRIGHT (c) 2008-2010 UCHICAGO ARGONNE, LLC | >> | Version: 1.0rc1 / SVN r982 | >> | Web: http://nek5000.mcs.anl.gov | >> | | >> \\----------------------------------------------------------/ >> >> >> Number of processors: 1 >> REAL wdsize : 8 >> INTEGER wdsize : 4 >> >> >> Beginning session: >> /home/kamal/neksamples/mine/box.rea >> >> >> timer accuracy: 0.0000000E+00 sec >> >> read .rea file >> nelgt/nelgv/lelt: 15 15 15 >> lx1 /lx2 /lx3 : 8 6 8 >> >> mapping elements to processors >> 0 15 15 15 15 NELV >> RANK 0 IEG 1 2 3 4 5 6 7 8 >> 9 10 11 12 13 14 15 >> element load imbalance: 0 15 15 >> done :: mapping elements to processors >> >> 0 objects found >> done :: read .rea file 0.67091E-03 sec >> >> Reset the target Courant number to .5 >> setup mesh topology >> Right-handed check complete for 15 elements. OK. >> setvert2d: 8 252 792 252 252 >> call usrsetvert >> done :: usrsetvert >> >> gs_setup: 0 unique labels shared >> handle bytes (avg, min, max): 3972 3972 3972 >> buffer bytes (avg, min, max): 0 0 0 >> setupds time 1.9503E-04 seconds 0 8 252 15 >> 4 max multiplicity >> done :: setup mesh topology >> >> call usrdat >> done :: usrdat >> >> generate geometry data >> vol_t,vol_v: 1.9999999999999920 1.9999999999999920 >> done :: generate geometry data >> >> call usrdat2 >> done :: usrdat2 >> >> regenerate geometry data 1 >> vol_t,vol_v: 1.9999999999999938 1.9999999999999938 >> done :: regenerate geometry data 1 >> >> verify mesh topology >> 0.0000000000000000 4.0000000000000000 Xrange >> 0.0000000000000000 0.50000000000000000 Yrange >> 0.0000000000000000 0.0000000000000000 Zrange >> done :: verify mesh topology >> >> 103 Parameters from file:/home/kamal/neksamples/mine/box.rea >> 1 1.00000 p1 DENSITY >> 2 -20.0000 p2 VISCOS >> 7 1.00000 p7 RHOCP >> 8 1.00000 p8 CONDUCT >> 11 1000.0 p11 NSTEPS >> 12 -1.000000E-04 p12 DT >> 15 100.000 p15 IOSTEP >> 18 0.250000E-01 p18 GRID >> 19 -1.00000 p19 INTYPE >> 20 12.0000 p20 NORDER >> 21 0.100000E-10 p21 DIVERGENCE >> 22 0.100000E-11 p22 HELMHOLTZ >> 24 0.100000E-09 p24 TOLREL >> 25 0.100000E-09 p25 TOLABS >> 26 1.00000 p26 COURANT/NTAU >> 27 3.00000 p27 TORDER >> 28 0. p28 TORDER: mesh velocity (0: p28=p27) >> 43 1.00000 p43 0=semg/1=schwarz >> 66 4.00000 p66 output : <0=ascii, else binary >> 67 4.00000 p67 restart: <0=ascii, else binary >> 93 20.0000 p93 Number of previous pressure solns saved >> 94 5.00000 p94 start projecting velocity after p94 step >> 95 5.00000 p95 start projecting pressure after p95 step >> 96 1.00000 p96 u0 translational velocity (in .usr) >> 97 0.30000 p97 v0 translational velocity (in .usr) >> 99 3.00000 p99 dealiasing: <0--> off/3--> old/4--> new >> 102 1.00000 p102 Dump out divergence at each time step >> >> IFTRAN = T >> IFFLOW = T >> IFHEAT = F >> IFSPLIT = F >> IFLOMACH = F >> IFUSERVP = F >> IFUSERMV = F >> IFSTRS = F >> IFCHAR = F >> IFCYCLIC = F >> IFAXIS = F >> IFMVBD = F >> IFMELT = F >> IFMODEL = F >> IFKEPS = F >> IFMOAB = F >> IFNEKNEK = F >> IFSYNC = T >> >> IFVCOR = T >> IFINTQ = F >> IFCWUZ = F >> IFSWALL = F >> IFGEOM = F >> IFSURT = F >> IFWCNO = F >> >> IFTMSH for field 1 = F >> IFADVC for field 1 = T >> IFNONL for field 1 = F >> >> Dealiasing enabled, lxd= 12 >> >> Estimated eigenvalues >> EIGAA = 20.047633939712757 >> EIGGA = 46987.971345031350 >> EIGAE = 0.61685027506808487 >> EIGAS = 3.8461538461538464E-003 >> EIGGE = 46987.971345031350 >> EIGGS = 2.0000000000000000 >> >> verify mesh topology >> 0.0000000000000000 4.0000000000000000 Xrange >> 0.0000000000000000 0.50000000000000000 Yrange >> 0.0000000000000000 0.0000000000000000 Zrange >> done :: verify mesh topology >> >> E-solver strategy: 1 itr >> 0 15 BC FAIL >> EXIT: E INVALID BC FOUND in genfast 15 >> >> call exitt: dying ... >> >> backtrace(): obtained 9 stack frames. >> ./nek5000(print_stack_+0x1a) [0x4fe90a] >> ./nek5000(exitt_+0x20f) [0x5bc0af] >> ./nek5000(exitti_+0x12a) [0x5be72a] >> ./nek5000(gen_fast_+0x581) [0x4fa701] >> ./nek5000(set_overlap_+0x125) [0x4eb465] >> ./nek5000(nek_init_+0x82d) [0x41affd] >> ./nek5000(main+0x24) [0x419e54] >> /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf5) [0x7fd9f1f33de5] >> ./nek5000() [0x419e99] >> >> total elapsed time : 3.74889E-03 sec >> total solver time incl. I/O : 0.00000E+00 sec >> time/timestep : 0.00000E+00 sec >> CPU seconds/timestep/gridpt : 0.00000E+00 sec >> >> >> real 0m0.030s >> user 0m0.020s >> sys 0m0.000s >> >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > From nek5000-users at lists.mcs.anl.gov Tue Jan 14 10:28:07 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 14 Jan 2014 17:28:07 +0100 Subject: [Nek5000-users] Problem converting 2d to 3d Message-ID: Hi, I created a 2d rectangular mesh using genbox, then I tried to used n2to3 to convert this into a cylindrical pipe using circular sweep but I get errors while loading the .rea file . could some one help me fix this Thank you ******************************** base.rea 2 spatial dimension 1 number of fields # # Eddy case # Box -50 -5 nelx,nely,nelz for Box 0 10. 1.0 x0 x1 ratio 0 1 1.0 y0 y1 ratio v ,O , ,W , bc's *************************************** Input for n2to3 script ***************************************** Input old (source) file name: eddy_uv Input new (output) file name: fg For ASCII output only: 0; For .rea/.re2: 1 1 input number of levels: (1, 2, 3,...; < 0 for circular sweep.): -2 input z min: 0 input z max: 1 input gain (0=custom,1=uniform,other=geometric spacing): 1 This is for CEM: yes or no: no Enter Z (5) boundary condition (P,v,O): W Enter Z (6) boundary condition (v,O): W this is cbz: W W <--- F 0 1 ifheat 2000 elements written to fg.rea 2000 elements written to fg.re2 when I use genmap or try to launch the mesh in prex I get error ***************************************************************** Input (.rea) file name: fg Input mesh tolerance (default 0.2): NOTE: smaller is better, but generous is more forgiving for bad meshes. 0.2 reading .rea file data ... reading .re2 file data ... start locglob_lexico: 8 2000 16000 0.20000000000000001 locglob: 1 1 16000 locglob: 2 104 16000 locglob: 3 1192 16000 locglob: 1 3012 16000 locglob: 2 3025 16000 locglob: 3 3031 16000 locglob: 1 3031 16000 locglob: 2 3031 16000 locglob: 3 3031 16000 1 2 4 Matrix: SELF!! 1 SELF!! 1 2 1 12 2 SELF!! 23 24 23 34 cont: SELF!! 1 ?? ABORT: SELF-CHK 1 5 1 0 Try to tighten the mesh tolerance! 0 quit ***************************************************************************************** From nek5000-users at lists.mcs.anl.gov Tue Jan 14 14:04:11 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 14 Jan 2014 20:04:11 +0000 Subject: [Nek5000-users] Pipe with expansion Message-ID: Kamal, I've added an example for a step-type expansion in a pipe. New example directory is nek5_svn/examples/expansion, with a README. If you want a standard diffuser, I would use mesh-morphing, as outlined in the nek primer, which can be found on this page: http://nek5000.mcs.anl.gov/index.php/UG#Documentation I've also automated our turbulent outflow bc treatment -- one simply provides an expansion factor (typically ~ 1.5) and two persistent arrays to turb_outflow(), which is now in navier5.f. This can be useful when very strong vortices are leaving the domain, which is possible for certain diffuser flow conditions (and others). Paul ________________________________________ From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] Sent: Monday, January 13, 2014 3:35 AM To: nek5000-users at lists.mcs.anl.gov Subject: [Nek5000-users] Creating a Mesh Hi Can some one please help me in this because I am new to nek 1) How can I create a .rea for a specific geometry say ' A sudden expansion pipe ' or a ' Diverging pipe ' 2) What tool I should use to create that mesh. Thank you kamal _______________________________________________ Nek5000-users mailing list Nek5000-users at lists.mcs.anl.gov https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users From nek5000-users at lists.mcs.anl.gov Tue Jan 14 14:09:27 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 14 Jan 2014 21:09:27 +0100 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: Message-ID: Hi Paul, Thanks a lot for the update. I will take a look at as soon as possible and keep you updated with it. Thank you, Kamal On Jan 14, 2014, at 9:04 PM, nek5000-users at lists.mcs.anl.gov wrote: > Kamal, > > I've added an example for a step-type expansion in a pipe. New example directory > is nek5_svn/examples/expansion, with a README. > > If you want a standard diffuser, I would use mesh-morphing, as outlined in the > nek primer, which can be found on this page: > > http://nek5000.mcs.anl.gov/index.php/UG#Documentation > > I've also automated our turbulent outflow bc treatment -- one simply provides an > expansion factor (typically ~ 1.5) and two persistent arrays to turb_outflow(), which > is now in navier5.f. This can be useful when very strong vortices are leaving the > domain, which is possible for certain diffuser flow conditions (and others). > > Paul > ________________________________________ > From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] > Sent: Monday, January 13, 2014 3:35 AM > To: nek5000-users at lists.mcs.anl.gov > Subject: [Nek5000-users] Creating a Mesh > > Hi > > Can some one please help me in this because I am new to nek > > 1) How can I create a .rea for a specific geometry say ' A sudden > expansion pipe ' or a ' Diverging pipe ' > > 2) What tool I should use to create that mesh. > > > Thank you > > > kamal > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users From nek5000-users at lists.mcs.anl.gov Wed Jan 15 03:45:44 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Wed, 15 Jan 2014 15:15:44 +0530 Subject: [Nek5000-users] Computing higher order derivatives Message-ID: Hello For doing stability analysis I need upto third derivatives of velocity. Is this already available in nek ? I tried to compute derivatives of the nek solution using chebfun but the second and higher derivatives are coming out to be discontinuous ? This is expected I suppose, since the solution is only C^0. Can I repeatedly use gradm1 to get higher derivatives ? Does gradm1 do some projection ? Thanks praveen -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Wed Jan 15 03:48:49 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Wed, 15 Jan 2014 10:48:49 +0100 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: Message-ID: Hi Paul, I looked at the example and it looks very helpful, but for a sudden expansion we have only two parts (i.e) the inlet pipe and the outlet pipe. Whereas in a diverging pipe we have three section (i.e,) The inlet pipe, Diverging section and the outlet pipe. Is it possible for me to create a 2D diverging section using mesh modification and revolve it around the centre axis to get a 3d diverging pipe ? or should I apply the mesh modification directly to the 3d sudden expansion pipe using usrdat2() ? Thanks, Kamal On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: > Hi Paul, > > Thanks a lot for the update. I will take a look at as soon as possible and keep you updated with it. > > Thank you, > > Kamal > > On Jan 14, 2014, at 9:04 PM, nek5000-users at lists.mcs.anl.gov wrote: > >> Kamal, >> >> I've added an example for a step-type expansion in a pipe. New example directory >> is nek5_svn/examples/expansion, with a README. >> >> If you want a standard diffuser, I would use mesh-morphing, as outlined in the >> nek primer, which can be found on this page: >> >> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >> >> I've also automated our turbulent outflow bc treatment -- one simply provides an >> expansion factor (typically ~ 1.5) and two persistent arrays to turb_outflow(), which >> is now in navier5.f. This can be useful when very strong vortices are leaving the >> domain, which is possible for certain diffuser flow conditions (and others). >> >> Paul >> ________________________________________ >> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >> Sent: Monday, January 13, 2014 3:35 AM >> To: nek5000-users at lists.mcs.anl.gov >> Subject: [Nek5000-users] Creating a Mesh >> >> Hi >> >> Can some one please help me in this because I am new to nek >> >> 1) How can I create a .rea for a specific geometry say ' A sudden >> expansion pipe ' or a ' Diverging pipe ' >> >> 2) What tool I should use to create that mesh. >> >> >> Thank you >> >> >> kamal >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users From nek5000-users at lists.mcs.anl.gov Wed Jan 15 05:14:21 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Wed, 15 Jan 2014 05:14:21 -0600 (CST) Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: Message-ID: Hi Kamal, For the geometry you describe, I would apply mesh morphing to a standard straight pipe. You can create such a pipe using a subset of the mkmesh script provided in the expansion example. If your transition region is conical, then I woud make certain that the change in slope occurs at element boundaries, i.e., as in the half cross-section depicted below: _______________ /| | | / | | | /| | | | ________________/ | | | | | | | | | | | | | | | | | | | | +-----+-----+---+--+---+------+------+----> z Paul On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > Hi Paul, > > I looked at the example and it looks very helpful, but for a sudden expansion > we have only two parts (i.e) the inlet pipe and the outlet pipe. Whereas in a > diverging pipe we have three section (i.e,) The inlet pipe, Diverging section > and the outlet pipe. > > > Is it possible for me to create a 2D diverging section using mesh > modification and revolve it around the centre axis to get a 3d diverging pipe > ? > > > or should I apply the mesh modification directly to the 3d sudden expansion > pipe using usrdat2() ? > > Thanks, > Kamal > > > On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >> Hi Paul, >> >> Thanks a lot for the update. I will take a look at as soon as possible and >> keep you updated with it. >> >> Thank you, >> >> Kamal >> >> On Jan 14, 2014, at 9:04 PM, nek5000-users at lists.mcs.anl.gov wrote: >> >>> Kamal, >>> >>> I've added an example for a step-type expansion in a pipe. New example >>> directory >>> is nek5_svn/examples/expansion, with a README. >>> >>> If you want a standard diffuser, I would use mesh-morphing, as outlined in >>> the >>> nek primer, which can be found on this page: >>> >>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>> >>> I've also automated our turbulent outflow bc treatment -- one simply >>> provides an >>> expansion factor (typically ~ 1.5) and two persistent arrays to >>> turb_outflow(), which >>> is now in navier5.f. This can be useful when very strong vortices are >>> leaving the >>> domain, which is possible for certain diffuser flow conditions (and >>> others). >>> >>> Paul >>> ________________________________________ >>> From: nek5000-users-bounces at lists.mcs.anl.gov >>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>> Sent: Monday, January 13, 2014 3:35 AM >>> To: nek5000-users at lists.mcs.anl.gov >>> Subject: [Nek5000-users] Creating a Mesh >>> >>> Hi >>> >>> Can some one please help me in this because I am new to nek >>> >>> 1) How can I create a .rea for a specific geometry say ' A sudden >>> expansion pipe ' or a ' Diverging pipe ' >>> >>> 2) What tool I should use to create that mesh. >>> >>> >>> Thank you >>> >>> >>> kamal >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > From nek5000-users at lists.mcs.anl.gov Wed Jan 15 05:22:50 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Wed, 15 Jan 2014 05:22:50 -0600 (CST) Subject: [Nek5000-users] Computing higher order derivatives In-Reply-To: References: Message-ID: Hi Praveen, Correct, the functions are only C^0 continuous. However, if the solution is C-infinity, the SEM will converge exponentially fast to the continuous solution. When taking such high-order derivatives, it's a good idea to be working in the full precision of the solution --- are you postprocessing when you apply chebfun? If so, make certain that your nek output data has full 64-bit precision (typ. 15 digits). Another approach you could try would be to perform, say, a least squares fit or other type of projection onto a C-infinity basis (e.g., Fourier, iff your function is periodic) and then differentiate that. Paul On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > Hello > For doing stability analysis I need upto third derivatives of velocity. Is > this already available in nek ? I tried to compute derivatives of the nek > solution using chebfun but the second and higher derivatives are coming out > to be discontinuous ? This is expected I suppose, since the solution is > only C^0. Can I repeatedly use gradm1 to get higher derivatives ? Does > gradm1 do some projection ? > > Thanks > praveen > From nek5000-users at lists.mcs.anl.gov Wed Jan 15 06:54:37 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Wed, 15 Jan 2014 06:54:37 -0600 (CST) Subject: [Nek5000-users] Computing higher order derivatives In-Reply-To: References: Message-ID: Hi Praveen, To compute continuous weak approximations to du/dy (say), you would do the following: call gradm1(ux,uy,uz,u) n = nx1*ny1*nz1*nelv call col2 (uy,bm1,n) call dssum (uy,nx1,ny1,nz1) call col2 (uy,binvm1,n) assuming all arrays appropriately declared. Paul On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > > Hi Praveen, > > Correct, the functions are only C^0 continuous. However, > if the solution is C-infinity, the SEM will > converge exponentially fast to the continuous solution. > > When taking such high-order derivatives, it's a good idea > to be working in the full precision of the solution --- are > you postprocessing when you apply chebfun? If so, make certain > that your nek output data has full 64-bit precision (typ. 15 digits). > > Another approach you could try would be to perform, say, a > least squares fit or other type of projection onto a C-infinity > basis (e.g., Fourier, iff your function is periodic) and then > differentiate that. > > Paul > > > On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > >> Hello >> For doing stability analysis I need upto third derivatives of velocity. Is >> this already available in nek ? I tried to compute derivatives of the nek >> solution using chebfun but the second and higher derivatives are coming out >> to be discontinuous ? This is expected I suppose, since the solution is >> only C^0. Can I repeatedly use gradm1 to get higher derivatives ? Does >> gradm1 do some projection ? >> >> Thanks >> praveen >> > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > From nek5000-users at lists.mcs.anl.gov Wed Jan 15 09:52:08 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Wed, 15 Jan 2014 16:52:08 +0100 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: Message-ID: Hi Paul, I will try that mapping, I created a straight pipe to do some simulations. 1) Is there a way to check my spectral convergence, so that I can do some mesh convergence study? 2) Is there a way to plot the kinetic energy in the flow ? Thank you, Kamal On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: > > Hi Kamal, > > For the geometry you describe, I would apply mesh morphing > to a standard straight pipe. You can create such a pipe > using a subset of the mkmesh script provided in the expansion > example. > > If your transition region is conical, then I woud make > certain that the change in slope occurs at element boundaries, > i.e., as in the half cross-section depicted below: > > _______________ > /| | | > / | | | > /| | | | > ________________/ | | | | > | | | | | | | | > | | | | | | | | > +-----+-----+---+--+---+------+------+----> z > > > Paul > > > > On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > >> Hi Paul, >> >> I looked at the example and it looks very helpful, but for a sudden >> expansion we have only two parts (i.e) the inlet pipe and the outlet >> pipe. Whereas in a diverging pipe we have three section (i.e,) The >> inlet pipe, Diverging section and the outlet pipe. >> >> >> Is it possible for me to create a 2D diverging section using mesh >> modification and revolve it around the centre axis to get a 3d >> diverging pipe ? >> >> >> or should I apply the mesh modification directly to the 3d sudden >> expansion pipe using usrdat2() ? >> >> Thanks, >> Kamal >> >> >> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>> Hi Paul, >>> >>> Thanks a lot for the update. I will take a look at as soon as >>> possible and keep you updated with it. >>> >>> Thank you, >>> >>> Kamal >>> >>> On Jan 14, 2014, at 9:04 PM, nek5000-users at lists.mcs.anl.gov wrote: >>> >>>> Kamal, >>>> >>>> I've added an example for a step-type expansion in a pipe. New >>>> example directory >>>> is nek5_svn/examples/expansion, with a README. >>>> >>>> If you want a standard diffuser, I would use mesh-morphing, as >>>> outlined in the >>>> nek primer, which can be found on this page: >>>> >>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>> >>>> I've also automated our turbulent outflow bc treatment -- one >>>> simply provides an >>>> expansion factor (typically ~ 1.5) and two persistent arrays to >>>> turb_outflow(), which >>>> is now in navier5.f. This can be useful when very strong >>>> vortices are leaving the >>>> domain, which is possible for certain diffuser flow conditions (and >>>> others). >>>> >>>> Paul >>>> ________________________________________ >>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>> Sent: Monday, January 13, 2014 3:35 AM >>>> To: nek5000-users at lists.mcs.anl.gov >>>> Subject: [Nek5000-users] Creating a Mesh >>>> >>>> Hi >>>> >>>> Can some one please help me in this because I am new to nek >>>> >>>> 1) How can I create a .rea for a specific geometry say ' A sudden >>>> expansion pipe ' or a ' Diverging pipe ' >>>> >>>> 2) What tool I should use to create that mesh. >>>> >>>> >>>> Thank you >>>> >>>> >>>> kamal >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users From nek5000-users at lists.mcs.anl.gov Wed Jan 15 06:42:30 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Wed, 15 Jan 2014 18:12:30 +0530 Subject: [Nek5000-users] Computing higher order derivatives In-Reply-To: References: Message-ID: On Wed, Jan 15, 2014 at 4:52 PM, wrote: > Hi Praveen, > > Correct, the functions are only C^0 continuous. However, > if the solution is C-infinity, the SEM will > converge exponentially fast to the continuous solution. > > When taking such high-order derivatives, it's a good idea > to be working in the full precision of the solution --- are > you postprocessing when you apply chebfun? If so, make certain > that your nek output data has full 64-bit precision (typ. 15 digits). > > Another approach you could try would be to perform, say, a > least squares fit or other type of projection onto a C-infinity > basis (e.g., Fourier, iff your function is periodic) and then > differentiate that. > > Paul > Hi Paul My problem is flow in a channel and I want to study some stability of 1-d velocity profile. In usrchk, I write the GLL nodes and solutions to a file with some 14-15 decimal places. In matlab I construct a piecwise barycentric lagrange formula. This is used by chebfun which automatically constructs a piecewise chebyshev approximation. It exactly and automatically recognizes the element boundaries !!! chebfun can also construct a single chebyshev approximation but needs ~65000 nodes and the higher derivatives have large error at the end points. Is it possible to find weak derivatives inside nek, e.g, find g such that int(g * phi) = int(du/dy * phi) for all phi Then g will give a continuous approximation to du/dy. Thanks praveen -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Wed Jan 15 09:50:38 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Wed, 15 Jan 2014 21:20:38 +0530 Subject: [Nek5000-users] Computing higher order derivatives In-Reply-To: References: Message-ID: On Wed, Jan 15, 2014 at 6:24 PM, wrote: > Hi Praveen, > > To compute continuous weak approximations to du/dy (say), you > would do the following: > > call gradm1(ux,uy,uz,u) > > n = nx1*ny1*nz1*nelv > call col2 (uy,bm1,n) > call dssum (uy,nx1,ny1,nz1) > call col2 (uy,binvm1,n) > > assuming all arrays appropriately declared. > Thank you. I will try this. I realized that I am saving the solution in 4 bytes which could lead to loss of precision. I tried to save the averaged solution in 8 bytes with following code in usrchk param(63) = 8.0 call avg_all() param(63) = 0.0 But the "avg*" files still are not saved in 8 bytes. If I set param(63)=8 in rea file then it works. Best praveen -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Wed Jan 15 16:26:20 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Wed, 15 Jan 2014 23:26:20 +0100 Subject: [Nek5000-users] prex question In-Reply-To: References: Message-ID: Hi Paul, I have another question about the ext_cyl example to construct a refined mesh. I want to refine the mesh around the cylinder, and I found in Nek5000 primer.pdf an example to create this kind of mesh x2d.rea 2 spatial dimension 1 number of fields # # comments # # #======================================================== # Y cYlinder 3 -24 1 nelr,nel_theta,nelz .5 .3 x0,y0 - center of cylinder ccbb descriptors: c-cyl, o-oct, b-box (1 character + space) .5 .55 .7 .8 r0 r1 ... r_nelr 0 1 1 theta0/2pi theta1/2pi ratio v ,W ,E ,E , bc?s (3 characters + comma) My question concerns about the input file x2d.rea. If I replace x2d.rea by import.rea in the case of ext_cyl. Will the new built mesh replace the old one? or It will create some strange mesh. How can I specify the boundary condition for the cylinder without using pretex graphically. I always have some graphic issues with pretex and postx on ubuntu 12.04. Can you put the file which generates the mesh around the cylinder on line? Thank you very much! Best regards Zhenlan On Sun, Nov 3, 2013 at 8:28 PM, wrote: > > Hi Tubois, > > 11 SET ENTIRE LEVEL applies the next selected > boundary condition to any _remaining_ boundaries for which > BCs have yet to be defined. > > In this case, that is just the BCs on the top and bottom > of the domain, since the inlet and outlet were prescribed > in the box file, while the sides were left blank. The > cylinder itself inherits and retains its boundary conditions > from the "import.rea" file. > > Does this clarify? > > Best, Paul > > > ----- Original Message ----- > From: nek5000-users at lists.mcs.anl.gov > To: nek5000-users at lists.mcs.anl.gov > Sent: Sunday, November 3, 2013 11:35:36 AM > Subject: Re: [Nek5000-users] prex question > > > > Hi Paul, > > > Thank you very much! Just need a confirm about your mesh. > 11 SET ENTIRE LEVEL > 1 PERIODIC-AUTO > means to set the periodic boundary condition for the box except the inlet > already set in fpcyl.box? > n Is this a lattice for hex-close-packed spheres?: > So the boundary condition for the circle will be set to walls > automatically? > > > Thank you! > > > Tubois > > > > > > On Sun, Nov 3, 2013 at 5:46 PM, < nek5000-users at lists.mcs.anl.gov > wrote: > > > > Hi Tubois, > > I've just updated this example and have included a script that appears > to work. > > I recommend moving your existing ext_cyl directory to, say, ext_cyl.1, > and then svn update ext_cyl. > > Then, in the new ext_cyl directory you should be able to type: > > mkmesh > > > The README file is also updated. Have a look at mkmesh and you > can see the basic steps. > > Paul > > > > > ----- Original Message ----- > From: nek5000-users at lists.mcs.anl.gov > To: nek5000-users at lists.mcs.anl.gov > Sent: Sunday, November 3, 2013 10:00:17 AM > Subject: [Nek5000-users] prex question > > > > Hello everyone, > > > 1, I am trying to create the mesh of the example ext_cyl with genbox, and > pretek. After consulting the email archives online, I almost got it works. > The question lies on mesh-merging. I used pretex. The commands is listed as > follows. > > > I got a mesh ext_cyl.rea identical to the one in the example, when I > visualized it with postx. However, when I use xxdiff to examine it, I found > several differences. > BOUNDARY CONDITIONS: > FLUID BOUNDARY CONDITIONS: > 11 0.00000 0.00000 ..... > For the file in the example, this line is > P 11 1337.00 3.00000 ...... > > > So which step did I missed? To set the BC in pretek? Can someone gives a > detailed command lines? > > > 2, About creating the mesh, the wiki says that Nek5000 works with Moab > Cubit, but this software is not free of charge. Is there any other free > software for meshing? In the archive, I found the discussion about > converting Gambit (we have Gambit in school) mesh to rea. The guy left an > email address cmeador at tamu.edu , which is no more valid. > > > Thank you very much! > > > Best regards > > > Tubois > ================================================================== > > > Choose a Name for This session: > ext_cyl > > Beginning Session ext_cyl > 1 READ PREVIOUS PARAMETERS > 2 TYPE IN NEW PARAMETERS > 3 CONJ. HEAT TRANSFER MERGE > Choose item: > 1 > 1 > Enter name of previous session > box.rea > 1 BUILD FROM FILE > 2 BUILD INTERACTIVELY > Choose item: > 1 > 1 > Enter name of previous session > (Default= box.rea ) > I pressed ENTER > > > > Will Read Mesh and B.C. data from box.rea > Reading Element 29 [ 1C] > Reading Element 58 [ 1f] > Reading Element 87 [ 1I] > Reading Element 116 [ 1l] > Reading Element 145 [ 1O] > Reading Element 174 [ 1r] > Reading Element 203 [ 1U] > Reading Element 232 [ 1x] > Reading Element 261 [ 1a] > Reading Element 290 [ 1D] > Reading Element 319 [ 1g] > Reading Element 348 [ 1J] > Reading Element 377 [ 1m] > Reading Element 406 [ 1P] > Reading Element 435 [ 1s] > Reading Element 464 [ 1V] > Reading Element 493 [ 1y] > Reading Element 522 [ 1b] > Reading Element 551 [ 1E] > Reading Element 580 [ 1h] > Reading Element 609 [ 1K] > Reading Element 638 [ 1n] > Reading Element 667 [ 1Q] > Reading Element 696 [ 1t] > Reading Element 725 [ 1W] > Reading Element 754 [ 1z] > Reading Element 783 [ 1c] > Reading Element 812 [ 1F] > Reading Element 841 [ 1i] > Reading Element 870 [ 1L] > Reading Element 899 [ 1o] > Reading Element 928 [ 1R] > Reading Element 957 [ 1u] > Reading Element 986 [ 1X] > Reading Element 1015 [ 1A] > Reading Element 1044 [ 1d] > Reading Element 1073 [ 1G] > Reading Element 1102 [ 1j] > Reading Element 1131 [ 1M] > Reading Element 1160 [ 1p] > Reading Element 1189 [ 1S] > Reading Element 1218 [ 1v] > Reading Element 1247 [ 1Y] > Reading Element 1276 [ 1B] > Reading Element 1305 [ 1e] > Reading Element 1334 [ 1H] > Reading Element 1363 [ 1k] > Reading Element 1392 [ 1N] > Reading Element 1421 [ 1q] > Reading Element 1450 [ 1T] > drwobjs: 0 > Showing only 90 elements of 1456 > *** BUILD MENU *** > inside gencen 1456 F 4 > done gencen 1456 > 1 END ELEMENTS > 2 MODIFY ELEMENT > 3 GLOBAL REFINE > 4 CURVE SIDES > 5 DELETE ELEMENT > 6 ZOOM > 7 SET GRID > 8 DEFINE OBJECT > 9 REDRAW MESH > 10 IMPORT MESH > 11 IMPORT VTK MESH > 12 IMPORT vtx MESH > 13 REFLECT MESH > Choose item: > 10 > > 10 > input name of new .rea file > import.rea > > Would you like to displace existing elements in box? > y > > Found 80 curve sides. > IFLD: 1 1 T F > ***** FLUID BOUNDARY CONDITIONS ***** > ***** FLUID BOUNDARY CONDITIONS *****$ > This is nel,ncurve old: 1456 0 > This is nel,ncurve new: 1536 80 > inside gencen 1536 F 4 > done gencen 1536 > X min/max of new elements: -1.200000 1.200001 > Y min/max of new elements: -1.200000 1.200000 > NO KEEP: 514 F -1.0500000 -1.0500000 0.0000000 > NO KEEP: 515 F -0.75000000 -1.0500000 0.0000000 > NO KEEP: 516 F -0.45000002 -1.0500000 0.0000000 > NO KEEP: 517 F -0.15000001 -1.0500000 0.0000000 > NO KEEP: 518 F 0.15000001 -1.0500000 0.0000000 > NO KEEP: 519 F 0.45000002 -1.0500000 0.0000000 > NO KEEP: 520 F 0.75000000 -1.0500000 0.0000000 > NO KEEP: 521 F 1.0500000 -1.0500000 0.0000000 > NO KEEP: 570 F -1.0500000 -0.75000000 0.0000000 > NO KEEP: 571 F -0.75000000 -0.75000000 0.0000000 > NO KEEP: 572 F -0.45000002 -0.75000000 0.0000000 > NO KEEP: 573 F -0.15000001 -0.75000000 0.0000000 > NO KEEP: 574 F 0.15000001 -0.75000000 0.0000000 > NO KEEP: 575 F 0.45000002 -0.75000000 0.0000000 > NO KEEP: 576 F 0.75000000 -0.75000000 0.0000000 > NO KEEP: 577 F 1.0500000 -0.75000000 0.0000000 > NO KEEP: 626 F -1.0500000 -0.45000002 0.0000000 > NO KEEP: 627 F -0.75000000 -0.45000002 0.0000000 > NO KEEP: 628 F -0.45000002 -0.45000002 0.0000000 > NO KEEP: 629 F -0.15000001 -0.45000002 0.0000000 > NO KEEP: 630 F 0.15000001 -0.45000002 0.0000000 > NO KEEP: 631 F 0.45000002 -0.45000002 0.0000000 > NO KEEP: 632 F 0.75000000 -0.45000002 0.0000000 > NO KEEP: 633 F 1.0500000 -0.45000002 0.0000000 > NO KEEP: 682 F -1.0500000 -0.15000001 0.0000000 > NO KEEP: 683 F -0.75000000 -0.15000001 0.0000000 > NO KEEP: 684 F -0.45000002 -0.15000001 0.0000000 > NO KEEP: 685 F -0.15000001 -0.15000001 0.0000000 > NO KEEP: 686 F 0.15000001 -0.15000001 0.0000000 > NO KEEP: 687 F 0.45000002 -0.15000001 0.0000000 > NO KEEP: 688 F 0.75000000 -0.15000001 0.0000000 > NO KEEP: 689 F 1.0500000 -0.15000001 0.0000000 > NO KEEP: 738 F -1.0500000 0.15000001 0.0000000 > NO KEEP: 739 F -0.75000000 0.15000001 0.0000000 > NO KEEP: 740 F -0.45000002 0.15000001 0.0000000 > NO KEEP: 741 F -0.15000001 0.15000001 0.0000000 > NO KEEP: 742 F 0.15000001 0.15000001 0.0000000 > NO KEEP: 743 F 0.45000002 0.15000001 0.0000000 > NO KEEP: 744 F 0.75000000 0.15000001 0.0000000 > NO KEEP: 745 F 1.0500000 0.15000001 0.0000000 > NO KEEP: 794 F -1.0500000 0.45000002 0.0000000 > NO KEEP: 795 F -0.75000000 0.45000002 0.0000000 > NO KEEP: 796 F -0.45000002 0.45000002 0.0000000 > NO KEEP: 797 F -0.15000001 0.45000002 0.0000000 > NO KEEP: 798 F 0.15000001 0.45000002 0.0000000 > NO KEEP: 799 F 0.45000002 0.45000002 0.0000000 > NO KEEP: 800 F 0.75000000 0.45000002 0.0000000 > NO KEEP: 801 F 1.0500000 0.45000002 0.0000000 > NO KEEP: 850 F -1.0500000 0.75000000 0.0000000 > NO KEEP: 851 F -0.75000000 0.75000000 0.0000000 > NO KEEP: 852 F -0.45000002 0.75000000 0.0000000 > NO KEEP: 853 F -0.15000001 0.75000000 0.0000000 > NO KEEP: 854 F 0.15000001 0.75000000 0.0000000 > NO KEEP: 855 F 0.45000002 0.75000000 0.0000000 > NO KEEP: 856 F 0.75000000 0.75000000 0.0000000 > NO KEEP: 857 F 1.0500000 0.75000000 0.0000000 > NO KEEP: 906 F -1.0500000 1.0500000 0.0000000 > NO KEEP: 907 F -0.75000000 1.0500000 0.0000000 > NO KEEP: 908 F -0.45000002 1.0500000 0.0000000 > NO KEEP: 909 F -0.15000001 1.0500000 0.0000000 > NO KEEP: 910 F 0.15000001 1.0500000 0.0000000 > NO KEEP: 911 F 0.45000002 1.0500000 0.0000000 > NO KEEP: 912 F 0.75000000 1.0500000 0.0000000 > NO KEEP: 913 F 1.0500000 1.0500000 0.0000000 > Deleting element 514 of 1536. > Deleting element 515 of 1536. > Deleting element 516 of 1536. > Deleting element 517 of 1536. > Deleting element 518 of 1536. > Deleting element 519 of 1536. > Deleting element 520 of 1536. > Deleting element 521 of 1536. > Deleting element 570 of 1536. > Deleting element 571 of 1536. > Deleting element 572 of 1536. > Deleting element 573 of 1536. > Deleting element 574 of 1536. > Deleting element 575 of 1536. > Deleting element 576 of 1536. > Deleting element 577 of 1536. > Deleting element 626 of 1536. > Deleting element 627 of 1536. > Deleting element 628 of 1536. > Deleting element 629 of 1536. > Deleting element 630 of 1536. > Deleting element 631 of 1536. > Deleting element 632 of 1536. > Deleting element 633 of 1536. > Deleting element 682 of 1536. > Deleting element 683 of 1536. > Deleting element 684 of 1536. > Deleting element 685 of 1536. > Deleting element 686 of 1536. > Deleting element 687 of 1536. > Deleting element 688 of 1536. > Deleting element 689 of 1536. > Deleting element 738 of 1536. > Deleting element 739 of 1536. > Deleting element 740 of 1536. > Deleting element 741 of 1536. > Deleting element 742 of 1536. > Deleting element 743 of 1536. > Deleting element 744 of 1536. > Deleting element 745 of 1536. > Deleting element 794 of 1536. > Deleting element 795 of 1536. > Deleting element 796 of 1536. > Deleting element 797 of 1536. > Deleting element 798 of 1536. > Deleting element 799 of 1536. > Deleting element 800 of 1536. > Deleting element 801 of 1536. > Deleting element 850 of 1536. > Deleting element 851 of 1536. > Deleting element 852 of 1536. > Deleting element 853 of 1536. > Deleting element 854 of 1536. > Deleting element 855 of 1536. > Deleting element 856 of 1536. > Deleting element 857 of 1536. > Deleting element 906 of 1536. > Deleting element 907 of 1536. > Deleting element 908 of 1536. > Deleting element 909 of 1536. > Deleting element 910 of 1536. > Deleting element 911 of 1536. > Deleting element 912 of 1536. > Deleting element 913 of 1536. > drwobjs: 0 > Showing only 90 elements of 1472 > drwobjs: 0 > inside gencen 1472 F 4 > done gencen 1472 > 1 END ELEMENTS > 2 MODIFY ELEMENT > 3 GLOBAL REFINE > 4 CURVE SIDES > 5 DELETE ELEMENT > 6 ZOOM > 7 SET GRID > 8 DEFINE OBJECT > 9 REDRAW MESH > 10 IMPORT MESH > 11 IMPORT VTK MESH > 12 IMPORT vtx MESH > 13 REFLECT MESH > Choose item: > 1 > > 1 > 1 ACCEPT MATL,QVOL > 2 SELECT ELEMENT > 3 SELECT MATL [ 0] > 4 SET MATL PROPS,Q > 5 SHOW MATL PROPS,Q > Choose it > > 1 > 1 > start locglob_lexico: 4 1472 5888 1.99999996E-02 > locglob: 1 1 5888 > locglob: 2 81 5888 > locglob: 1 1562 5888 > locglob: 2 1562 5888 > Performing unique_vertex2 self_chk 5888 > done locglob_lexico: 1562 1562 5888 5 > Performing makecell self_chk 5888 > > > *** MIDWAY BREAK MENU *** > ABORT to write build data to file and exit > SET B.C'S to continue > 1 SET BCs > 2 ABORT > Choose item: > > 2 > Generating Mesh Points for 1472 Elements > 1472 this is nel in prexit > Writing Parameters to file > Deleting tmp.* files. > Exiting session 4.59163468E-41 > > > > > > > > > > > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > -- Universit? Pierre et Marie Curie CNRS-LIMSI Campus d'Orsay 91403 ORSAY -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Fri Jan 17 04:05:28 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Fri, 17 Jan 2014 10:05:28 +0000 Subject: [Nek5000-users] Post processing bypass Message-ID: Dear All, A quick question; is there a way to run nek5000 in post-processing mode (i.e. with nsteps=0) BUT without re-generating the mesh? The use would be for example to carry out post-processing from large-scale simulation data from a high-performance computer on a less powerful computer (that is not able to re-generate the mesh without sufficient RAM, etc) Thank you, JP -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Fri Jan 17 04:55:11 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Fri, 17 Jan 2014 11:55:11 +0100 Subject: [Nek5000-users] Post processing bypass In-Reply-To: References: Message-ID: Hi Neks ! Is there a way to load a .fld file during a simulation (in the same way load_fld() does) but without doing a complete restart of all the variables ? Thanks for any help ! Holly From nek5000-users at lists.mcs.anl.gov Fri Jan 17 04:56:59 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Fri, 17 Jan 2014 11:56:59 +0100 Subject: [Nek5000-users] Load_fld() without restart In-Reply-To: References: Message-ID: Hi Neks ! Is there a way to load a .fld file during a simulation (in the same way load_fld() does) but without doing a complete restart of all the variables ? Thanks for any help ! Holly From nek5000-users at lists.mcs.anl.gov Fri Jan 17 07:14:51 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Fri, 17 Jan 2014 07:14:51 -0600 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: Message-ID: Kamal, 1) To check for convergence, run your simulation for increasing polynomial orders ( lx1 in the SIZE file) and measure some consistent quantity (drag, TKE, etc). You can plot this quantity against lx1 and this should give you a good picture of how you are converging (without needing to change the physical mesh). 2) If you weren't using temperature in your simulation, you could do put the following code snippet in your userchk c------------------------------------------- integer i, ntot ntot = nx1*ny1*nz1*nelv ! total number of points in simulation (on THIS processor) do i = 1,ntot t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + vz(i,1,1,1)**2) enddo ifto = .true. c------------------------------------------- I've assumed here that your density is unity. This computed kinetic energy point-wise and stores it in the temperature field. The part "ifto = .true." tells Nek to output the temperature field whenever it outputs a field file. You could then view this in visit just like you would the velocity field. Hope this helps! Josh On Wed, Jan 15, 2014 at 9:52 AM, wrote: > Hi Paul, > > I will try that mapping, I created a straight pipe to do some simulations. > > 1) Is there a way to check my spectral convergence, so that I can do some > mesh convergence study? > 2) Is there a way to plot the kinetic energy in the flow ? > > Thank you, > Kamal > > > > > On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: > >> >> Hi Kamal, >> >> For the geometry you describe, I would apply mesh morphing >> to a standard straight pipe. You can create such a pipe >> using a subset of the mkmesh script provided in the expansion >> example. >> >> If your transition region is conical, then I woud make >> certain that the change in slope occurs at element boundaries, >> i.e., as in the half cross-section depicted below: >> >> _______________ >> /| | | >> / | | | >> /| | | | >> ________________/ | | | | >> | | | | | | | | >> | | | | | | | | >> +-----+-----+---+--+---+------+------+----> z >> >> >> Paul >> >> >> >> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >> >> Hi Paul, >>> >>> I looked at the example and it looks very helpful, but for a sudden >>> expansion we have only two parts (i.e) the inlet pipe and the outlet pipe. >>> Whereas in a diverging pipe we have three section (i.e,) The inlet pipe, >>> Diverging section and the outlet pipe. >>> >>> >>> Is it possible for me to create a 2D diverging section using mesh >>> modification and revolve it around the centre axis to get a 3d diverging >>> pipe ? >>> >>> >>> or should I apply the mesh modification directly to the 3d sudden >>> expansion pipe using usrdat2() ? >>> >>> Thanks, >>> Kamal >>> >>> >>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>> >>>> Hi Paul, >>>> >>>> Thanks a lot for the update. I will take a look at as soon as possible >>>> and keep you updated with it. >>>> >>>> Thank you, >>>> >>>> Kamal >>>> >>>> On Jan 14, 2014, at 9:04 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>> Kamal, >>>>> >>>>> I've added an example for a step-type expansion in a pipe. New example >>>>> directory >>>>> is nek5_svn/examples/expansion, with a README. >>>>> >>>>> If you want a standard diffuser, I would use mesh-morphing, as >>>>> outlined in the >>>>> nek primer, which can be found on this page: >>>>> >>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>> >>>>> I've also automated our turbulent outflow bc treatment -- one simply >>>>> provides an >>>>> expansion factor (typically ~ 1.5) and two persistent arrays to >>>>> turb_outflow(), which >>>>> is now in navier5.f. This can be useful when very strong vortices >>>>> are leaving the >>>>> domain, which is possible for certain diffuser flow conditions (and >>>>> others). >>>>> >>>>> Paul >>>>> ________________________________________ >>>>> From: nek5000-users-bounces at lists.mcs.anl.gov [ >>>>> nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>> To: nek5000-users at lists.mcs.anl.gov >>>>> Subject: [Nek5000-users] Creating a Mesh >>>>> >>>>> Hi >>>>> >>>>> Can some one please help me in this because I am new to nek >>>>> >>>>> 1) How can I create a .rea for a specific geometry say ' A sudden >>>>> expansion pipe ' or a ' Diverging pipe ' >>>>> >>>>> 2) What tool I should use to create that mesh. >>>>> >>>>> >>>>> Thank you >>>>> >>>>> >>>>> kamal >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > -- Josh Camp "All that is necessary for the triumph of evil is that good men do nothing" -- Edmund Burke -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Fri Jan 17 07:21:35 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Fri, 17 Jan 2014 07:21:35 -0600 Subject: [Nek5000-users] Load_fld() without restart In-Reply-To: References: Message-ID: Hi Holly, If you wanted to load a .fld file without copying over your variables, you could do something like ! Create temporary storage real tmp1(lx1*ly1*lz1*lelv), tmp2(lx1*ly1*lz1*lelv), ... ! Copy simulation fields to temporary variables call copy(tmp1,vx,nx1*ny1*nz1*nelv) ... ! Load field file and do whatever work you want to do with it ! Copy simulation fields back to nek variables call copy(vx,tmp1,nx1*ny1*nz1*nelv) You should be able to use some of the Nek scratch arrays to store your temporary variables (instead of taking up more memory with the explicit declaration), but I'm not sure at the moment which scratch arrays load_fld() uses. - Josh On Fri, Jan 17, 2014 at 4:56 AM, wrote: > Hi Neks ! > > Is there a way to load a .fld file during a simulation (in the same way > load_fld() does) but without doing a complete restart of all the variables ? > > Thanks for any help ! > > Holly > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > -- Josh Camp "All that is necessary for the triumph of evil is that good men do nothing" -- Edmund Burke -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Fri Jan 17 07:24:38 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Fri, 17 Jan 2014 14:24:38 +0100 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: Message-ID: Hi Paul, Thanks paul. I tried working with the diverging mesh modification. I tried to use this form of equation to modify the mesh z = mx + b z = ny + c x = ( z - b ) / m y = (z - c) / n Do you think would work ? or is there any other way to input that ? Thanks, Kamal On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.gov wrote: > Kamal, > > 1) To check for convergence, run your simulation for increasing > polynomial orders ( lx1 in the SIZE file) and measure some consistent > quantity (drag, TKE, etc). You can plot this quantity against lx1 and > this should give you a good picture of how you are converging (without > needing to change the physical mesh). > > 2) If you weren't using temperature in your simulation, you could do > put the following code snippet in your userchk > > c------------------------------------------- > integer i, ntot > > ntot = nx1*ny1*nz1*nelv ! total number of points in simulation (on > THIS processor) > > do i = 1,ntot > t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + vz(i,1,1,1)**2) > enddo > > ifto = .true. > c------------------------------------------- > > I've assumed here that your density is unity. This computed kinetic > energy point-wise and stores it in the temperature field. The part > "ifto = .true." tells Nek to output the temperature field whenever it > outputs a field file. You could then view this in visit just like you > would the velocity field. > > Hope this helps! > > Josh > > > > > > On Wed, Jan 15, 2014 at 9:52 AM, > wrote: > > Hi Paul, > > I will try that mapping, I created a straight pipe to do some > simulations. > > 1) Is there a way to check my spectral convergence, so that I can > do some mesh convergence study? > 2) Is there a way to plot the kinetic energy in the flow ? > > Thank you, > Kamal > > > > > On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov > wrote: > > > Hi Kamal, > > For the geometry you describe, I would apply mesh morphing > to a standard straight pipe. You can create such a pipe > using a subset of the mkmesh script provided in the expansion > example. > > If your transition region is conical, then I woud make > certain that the change in slope occurs at element boundaries, > i.e., as in the half cross-section depicted below: > > _______________ > /| | | > / | | | > /| | | | > ________________/ | | | | > | | | | | | | | > | | | | | | | | > +-----+-----+---+--+---+------+------+----> z > > > Paul > > > > On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov > wrote: > > Hi Paul, > > I looked at the example and it looks very helpful, but for > a sudden expansion we have only two parts (i.e) the inlet > pipe and the outlet pipe. Whereas in a diverging pipe we > have three section (i.e,) The inlet pipe, Diverging > section and the outlet pipe. > > > Is it possible for me to create a 2D diverging section > using mesh modification and revolve it around the centre > axis to get a 3d diverging pipe ? > > > or should I apply the mesh modification directly to the 3d > sudden expansion pipe using usrdat2() ? > > Thanks, > Kamal > > > On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov > wrote: > > Hi Paul, > > Thanks a lot for the update. I will take a look at as > soon as possible and keep you updated with it. > > Thank you, > > Kamal > > On Jan 14, 2014, at 9:04 PM, > nek5000-users at lists.mcs.anl.gov > wrote: > > Kamal, > > I've added an example for a step-type expansion in > a pipe. New example directory > is nek5_svn/examples/expansion, with a README. > > If you want a standard diffuser, I would use > mesh-morphing, as outlined in the > nek primer, which can be found on this page: > > http://nek5000.mcs.anl.gov/index.php/UG#Documentation > > I've also automated our turbulent outflow bc > treatment -- one simply provides an > expansion factor (typically ~ 1.5) and two > persistent arrays to turb_outflow(), which > is now in navier5.f. This can be useful when > very strong vortices are leaving the > domain, which is possible for certain diffuser > flow conditions (and others). > > Paul > ________________________________________ > From: nek5000-users-bounces at lists.mcs.anl.gov > > [nek5000-users-bounces at lists.mcs.anl.gov > ] > on behalf of nek5000-users at lists.mcs.anl.gov > > [nek5000-users at lists.mcs.anl.gov > ] > Sent: Monday, January 13, 2014 3:35 AM > To: nek5000-users at lists.mcs.anl.gov > > Subject: [Nek5000-users] Creating a Mesh > > Hi > > Can some one please help me in this because I am > new to nek > > 1) How can I create a .rea for a specific geometry > say ' A sudden > expansion pipe ' or a ' Diverging pipe ' > > 2) What tool I should use to create that mesh. > > > Thank you > > > kamal > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > > > > -- > Josh Camp > > "All that is necessary for the triumph of evil is that good men do > nothing" -- Edmund Burke > > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Fri Jan 17 15:01:38 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Fri, 17 Jan 2014 22:01:38 +0100 Subject: [Nek5000-users] genbox question Message-ID: Hi, I am struggling with genbox to generate a mesh around the cylinder, which could be used in the example ext_cyl as the file import.rea, but with a mesh refined or more coarse. base.rea 2 spatial dimension 1 number of fields # # comments # # #======================================================== # Y cYlinder 3 -24 1 nelr,nel_theta,nelz .0 .0 x0,y0 - center of cylinder ccbb descriptors: c-cyl, o-oct, b-box (1 character + space) .5 .55 .7 .8 r0 r1 ... r_nelr 0 1 1 theta0/2pi theta1/2pi ratio E ,E ,E ,E , bc?s (3 characters + comma) I am wondering how to define the boundary condition here. E ,E ,E ,E , or E ,E ,E ,E ,W ? I slightly modified some lines in mknek to take into account of this new file, so everything can be run automatically. But I got a very strange mesh here. Some parts are missing. Can someone help me out? Just download these files and run ./mkmesh Thank you very much in advance. Tubois -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: box7.2d Type: application/octet-stream Size: 392 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: base.rea Type: application/octet-stream Size: 5139 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: fpcyl.box Type: application/octet-stream Size: 902 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: makenek Type: application/octet-stream Size: 1978 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: mkmesh Type: application/octet-stream Size: 652 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: visit0000.png Type: image/png Size: 44948 bytes Desc: not available URL: From nek5000-users at lists.mcs.anl.gov Sat Jan 18 06:36:25 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Sat, 18 Jan 2014 14:36:25 +0200 Subject: [Nek5000-users] turbulent 3d box In-Reply-To: References: , , , , , Message-ID: Dear Paul, Regarding the issue of DNS/LES. How I define what is the turbulence model is used? Thanks, Barak From nek5000-users at lists.mcs.anl.gov Sat Jan 18 12:14:19 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Sat, 18 Jan 2014 12:14:19 -0600 (CST) Subject: [Nek5000-users] turbulent 3d box In-Reply-To: References: , , , , , Message-ID: Personally, I'm partial to filtering (for lack of a better alternative at present). I'm running with lx1=8, say, I would set parameter 103 to 0.1 and parameter 101 to 1 in the .rea file. This would imply: Nth mode is reduced by 0.1 at the end of each timestep N-1st mode is reduced by 0.1*(1/4) at each step. The multimode filter (anytime p103>0 and p101>0) reduces the Nth mode by p103 and additional modes N-k, k=1,...,p101, by a quadratic fit. For LES, you probably want to remove energy from ~25% of the modes, with a smooth roll-off, as given by the quadratic fit. Thus, for lx1=12, I would take p101=2, which would result in modes N, N-1, and N-2 being reduced. Paul On Sat, 18 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > Dear Paul, > Regarding the issue of DNS/LES. How I define what is the turbulence model is > used? > Thanks, > Barak > > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > From nek5000-users at lists.mcs.anl.gov Sat Jan 18 12:17:05 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Sat, 18 Jan 2014 19:17:05 +0100 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: Message-ID: Dear Paul, I tried many ways to map my straight pipe geometry but it does not seem to work properly I used something like X = X + Z * tan ( alpha ) Y = Y + Z* tan (alpha ) even that dint work. could please help me with this Thank you Kamal. On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov wrote: > Hi Paul, > > Thanks paul. I tried working with the diverging mesh modification. > > I tried to use this form of equation to modify the mesh > > z = mx + b > z = ny + c > > x = ( z - b ) / m > y = (z - c) / n > > Do you think would work ? or is there any other way to input that ? > > Thanks, > > Kamal > > > On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.gov wrote: >> Kamal, >> >> 1) To check for convergence, run your simulation for increasing polynomial orders ( lx1 in the SIZE file) and measure some consistent quantity (drag, TKE, etc). You can plot this quantity against lx1 and this should give you a good picture of how you are converging (without needing to change the physical mesh). >> >> 2) If you weren't using temperature in your simulation, you could do put the following code snippet in your userchk >> >> c------------------------------------------- >> integer i, ntot >> >> ntot = nx1*ny1*nz1*nelv ! total number of points in simulation (on THIS processor) >> >> do i = 1,ntot >> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + vz(i,1,1,1)**2) >> enddo >> >> ifto = .true. >> c------------------------------------------- >> >> I've assumed here that your density is unity. This computed kinetic energy point-wise and stores it in the temperature field. The part "ifto = .true." tells Nek to output the temperature field whenever it outputs a field file. You could then view this in visit just like you would the velocity field. >> >> Hope this helps! >> >> Josh >> >> >> >> >> >> On Wed, Jan 15, 2014 at 9:52 AM, wrote: >> Hi Paul, >> >> I will try that mapping, I created a straight pipe to do some simulations. >> >> 1) Is there a way to check my spectral convergence, so that I can do some mesh convergence study? >> 2) Is there a way to plot the kinetic energy in the flow ? >> >> Thank you, >> Kamal >> >> >> >> >> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >> >> Hi Kamal, >> >> For the geometry you describe, I would apply mesh morphing >> to a standard straight pipe. You can create such a pipe >> using a subset of the mkmesh script provided in the expansion >> example. >> >> If your transition region is conical, then I woud make >> certain that the change in slope occurs at element boundaries, >> i.e., as in the half cross-section depicted below: >> >> _______________ >> /| | | >> / | | | >> /| | | | >> ________________/ | | | | >> | | | | | | | | >> | | | | | | | | >> +-----+-----+---+--+---+------+------+----> z >> >> >> Paul >> >> >> >> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >> >> Hi Paul, >> >> I looked at the example and it looks very helpful, but for a sudden expansion we have only two parts (i.e) the inlet pipe and the outlet pipe. Whereas in a diverging pipe we have three section (i.e,) The inlet pipe, Diverging section and the outlet pipe. >> >> >> Is it possible for me to create a 2D diverging section using mesh modification and revolve it around the centre axis to get a 3d diverging pipe ? >> >> >> or should I apply the mesh modification directly to the 3d sudden expansion pipe using usrdat2() ? >> >> Thanks, >> Kamal >> >> >> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >> Hi Paul, >> >> Thanks a lot for the update. I will take a look at as soon as possible and keep you updated with it. >> >> Thank you, >> >> Kamal >> >> On Jan 14, 2014, at 9:04 PM, nek5000-users at lists.mcs.anl.gov wrote: >> >> Kamal, >> >> I've added an example for a step-type expansion in a pipe. New example directory >> is nek5_svn/examples/expansion, with a README. >> >> If you want a standard diffuser, I would use mesh-morphing, as outlined in the >> nek primer, which can be found on this page: >> >> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >> >> I've also automated our turbulent outflow bc treatment -- one simply provides an >> expansion factor (typically ~ 1.5) and two persistent arrays to turb_outflow(), which >> is now in navier5.f. This can be useful when very strong vortices are leaving the >> domain, which is possible for certain diffuser flow conditions (and others). >> >> Paul >> ________________________________________ >> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >> Sent: Monday, January 13, 2014 3:35 AM >> To: nek5000-users at lists.mcs.anl.gov >> Subject: [Nek5000-users] Creating a Mesh >> >> Hi >> >> Can some one please help me in this because I am new to nek >> >> 1) How can I create a .rea for a specific geometry say ' A sudden >> expansion pipe ' or a ' Diverging pipe ' >> >> 2) What tool I should use to create that mesh. >> >> >> Thank you >> >> >> kamal >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> >> >> -- >> Josh Camp >> >> "All that is necessary for the triumph of evil is that good men do nothing" -- Edmund Burke >> >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Sat Jan 18 12:22:27 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Sat, 18 Jan 2014 18:22:27 +0000 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , Message-ID: Kamal, Have you looked at the peris example? The usr file there shows how to deform a pipe geometry. Paul ________________________________ From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] Sent: Saturday, January 18, 2014 12:17 PM To: nek5000-users at lists.mcs.anl.gov Subject: Re: [Nek5000-users] Pipe with expansion Dear Paul, I tried many ways to map my straight pipe geometry but it does not seem to work properly I used something like X = X + Z * tan ( alpha ) Y = Y + Z* tan (alpha ) even that dint work. could please help me with this Thank you Kamal. On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov wrote: Hi Paul, Thanks paul. I tried working with the diverging mesh modification. I tried to use this form of equation to modify the mesh z = mx + b z = ny + c x = ( z - b ) / m y = (z - c) / n Do you think would work ? or is there any other way to input that ? Thanks, Kamal On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.gov wrote: Kamal, 1) To check for convergence, run your simulation for increasing polynomial orders ( lx1 in the SIZE file) and measure some consistent quantity (drag, TKE, etc). You can plot this quantity against lx1 and this should give you a good picture of how you are converging (without needing to change the physical mesh). 2) If you weren't using temperature in your simulation, you could do put the following code snippet in your userchk c------------------------------------------- integer i, ntot ntot = nx1*ny1*nz1*nelv ! total number of points in simulation (on THIS processor) do i = 1,ntot t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + vz(i,1,1,1)**2) enddo ifto = .true. c------------------------------------------- I've assumed here that your density is unity. This computed kinetic energy point-wise and stores it in the temperature field. The part "ifto = .true." tells Nek to output the temperature field whenever it outputs a field file. You could then view this in visit just like you would the velocity field. Hope this helps! Josh On Wed, Jan 15, 2014 at 9:52 AM, > wrote: Hi Paul, I will try that mapping, I created a straight pipe to do some simulations. 1) Is there a way to check my spectral convergence, so that I can do some mesh convergence study? 2) Is there a way to plot the kinetic energy in the flow ? Thank you, Kamal On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: Hi Kamal, For the geometry you describe, I would apply mesh morphing to a standard straight pipe. You can create such a pipe using a subset of the mkmesh script provided in the expansion example. If your transition region is conical, then I woud make certain that the change in slope occurs at element boundaries, i.e., as in the half cross-section depicted below: _______________ /| | | / | | | /| | | | ________________/ | | | | | | | | | | | | | | | | | | | | +-----+-----+---+--+---+------+------+----> z Paul On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: Hi Paul, I looked at the example and it looks very helpful, but for a sudden expansion we have only two parts (i.e) the inlet pipe and the outlet pipe. Whereas in a diverging pipe we have three section (i.e,) The inlet pipe, Diverging section and the outlet pipe. Is it possible for me to create a 2D diverging section using mesh modification and revolve it around the centre axis to get a 3d diverging pipe ? or should I apply the mesh modification directly to the 3d sudden expansion pipe using usrdat2() ? Thanks, Kamal On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: Hi Paul, Thanks a lot for the update. I will take a look at as soon as possible and keep you updated with it. Thank you, Kamal On Jan 14, 2014, at 9:04 PM, nek5000-users at lists.mcs.anl.gov wrote: Kamal, I've added an example for a step-type expansion in a pipe. New example directory is nek5_svn/examples/expansion, with a README. If you want a standard diffuser, I would use mesh-morphing, as outlined in the nek primer, which can be found on this page: http://nek5000.mcs.anl.gov/index.php/UG#Documentation I've also automated our turbulent outflow bc treatment -- one simply provides an expansion factor (typically ~ 1.5) and two persistent arrays to turb_outflow(), which is now in navier5.f. This can be useful when very strong vortices are leaving the domain, which is possible for certain diffuser flow conditions (and others). Paul ________________________________________ From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] Sent: Monday, January 13, 2014 3:35 AM To: nek5000-users at lists.mcs.anl.gov Subject: [Nek5000-users] Creating a Mesh Hi Can some one please help me in this because I am new to nek 1) How can I create a .rea for a specific geometry say ' A sudden expansion pipe ' or a ' Diverging pipe ' 2) What tool I should use to create that mesh. Thank you kamal _______________________________________________ Nek5000-users mailing list Nek5000-users at lists.mcs.anl.gov https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users _______________________________________________ Nek5000-users mailing list Nek5000-users at lists.mcs.anl.gov https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users _______________________________________________ Nek5000-users mailing list Nek5000-users at lists.mcs.anl.gov https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users _______________________________________________ Nek5000-users mailing list Nek5000-users at lists.mcs.anl.gov https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users _______________________________________________ Nek5000-users mailing list Nek5000-users at lists.mcs.anl.gov https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users _______________________________________________ Nek5000-users mailing list Nek5000-users at lists.mcs.anl.gov https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users -- Josh Camp "All that is necessary for the triumph of evil is that good men do nothing" -- Edmund Burke _______________________________________________ Nek5000-users mailing list Nek5000-users at lists.mcs.anl.gov https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users _______________________________________________ Nek5000-users mailing list Nek5000-users at lists.mcs.anl.gov https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Sat Jan 18 12:26:08 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Sat, 18 Jan 2014 19:26:08 +0100 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , Message-ID: Hi Paul, I looked at the Helix and stenosis example but they are using cosine functions to deform I tried to use a tangent function but it bends the whole pipe. I dint look at peris example . I will take a look at it and let you know. Thank you Kamal On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov wrote: > > Kamal, > > Have you looked at the peris example? The usr file there shows how to deform > a pipe geometry. > > Paul > > From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] > Sent: Saturday, January 18, 2014 12:17 PM > To: nek5000-users at lists.mcs.anl.gov > Subject: Re: [Nek5000-users] Pipe with expansion > > Dear Paul, > > I tried many ways to map my straight pipe geometry but it does not seem to work properly > > I used something like > > X = X + Z * tan ( alpha ) > Y = Y + Z* tan (alpha ) > > > even that dint work. could please help me with this > > Thank you > > Kamal. > > On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov wrote: > >> Hi Paul, >> >> Thanks paul. I tried working with the diverging mesh modification. >> >> I tried to use this form of equation to modify the mesh >> >> z = mx + b >> z = ny + c >> >> x = ( z - b ) / m >> y = (z - c) / n >> >> Do you think would work ? or is there any other way to input that ? >> >> Thanks, >> >> Kamal >> >> >> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>> Kamal, >>> >>> 1) To check for convergence, run your simulation for increasing polynomial orders ( lx1 in the SIZE file) and measure some consistent quantity (drag, TKE, etc). You can plot this quantity against lx1 and this should give you a good picture of how you are converging (without needing to change the physical mesh). >>> >>> 2) If you weren't using temperature in your simulation, you could do put the following code snippet in your userchk >>> >>> c------------------------------------------- >>> integer i, ntot >>> >>> ntot = nx1*ny1*nz1*nelv ! total number of points in simulation (on THIS processor) >>> >>> do i = 1,ntot >>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + vz(i,1,1,1)**2) >>> enddo >>> >>> ifto = .true. >>> c------------------------------------------- >>> >>> I've assumed here that your density is unity. This computed kinetic energy point-wise and stores it in the temperature field. The part "ifto = .true." tells Nek to output the temperature field whenever it outputs a field file. You could then view this in visit just like you would the velocity field. >>> >>> Hope this helps! >>> >>> Josh >>> >>> >>> >>> >>> >>> On Wed, Jan 15, 2014 at 9:52 AM, wrote: >>> Hi Paul, >>> >>> I will try that mapping, I created a straight pipe to do some simulations. >>> >>> 1) Is there a way to check my spectral convergence, so that I can do some mesh convergence study? >>> 2) Is there a way to plot the kinetic energy in the flow ? >>> >>> Thank you, >>> Kamal >>> >>> >>> >>> >>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >>> >>> Hi Kamal, >>> >>> For the geometry you describe, I would apply mesh morphing >>> to a standard straight pipe. You can create such a pipe >>> using a subset of the mkmesh script provided in the expansion >>> example. >>> >>> If your transition region is conical, then I woud make >>> certain that the change in slope occurs at element boundaries, >>> i.e., as in the half cross-section depicted below: >>> >>> _______________ >>> /| | | >>> / | | | >>> /| | | | >>> ________________/ | | | | >>> | | | | | | | | >>> | | | | | | | | >>> +-----+-----+---+--+---+------+------+----> z >>> >>> >>> Paul >>> >>> >>> >>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>> >>> Hi Paul, >>> >>> I looked at the example and it looks very helpful, but for a sudden expansion we have only two parts (i.e) the inlet pipe and the outlet pipe. Whereas in a diverging pipe we have three section (i.e,) The inlet pipe, Diverging section and the outlet pipe. >>> >>> >>> Is it possible for me to create a 2D diverging section using mesh modification and revolve it around the centre axis to get a 3d diverging pipe ? >>> >>> >>> or should I apply the mesh modification directly to the 3d sudden expansion pipe using usrdat2() ? >>> >>> Thanks, >>> Kamal >>> >>> >>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>> Hi Paul, >>> >>> Thanks a lot for the update. I will take a look at as soon as possible and keep you updated with it. >>> >>> Thank you, >>> >>> Kamal >>> >>> On Jan 14, 2014, at 9:04 PM, nek5000-users at lists.mcs.anl.gov wrote: >>> >>> Kamal, >>> >>> I've added an example for a step-type expansion in a pipe. New example directory >>> is nek5_svn/examples/expansion, with a README. >>> >>> If you want a standard diffuser, I would use mesh-morphing, as outlined in the >>> nek primer, which can be found on this page: >>> >>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>> >>> I've also automated our turbulent outflow bc treatment -- one simply provides an >>> expansion factor (typically ~ 1.5) and two persistent arrays to turb_outflow(), which >>> is now in navier5.f. This can be useful when very strong vortices are leaving the >>> domain, which is possible for certain diffuser flow conditions (and others). >>> >>> Paul >>> ________________________________________ >>> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf ofnek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>> Sent: Monday, January 13, 2014 3:35 AM >>> To: nek5000-users at lists.mcs.anl.gov >>> Subject: [Nek5000-users] Creating a Mesh >>> >>> Hi >>> >>> Can some one please help me in this because I am new to nek >>> >>> 1) How can I create a .rea for a specific geometry say ' A sudden >>> expansion pipe ' or a ' Diverging pipe ' >>> >>> 2) What tool I should use to create that mesh. >>> >>> >>> Thank you >>> >>> >>> kamal >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> >>> >>> -- >>> Josh Camp >>> >>> "All that is necessary for the triumph of evil is that good men do nothing" -- Edmund Burke >>> >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Sun Jan 19 11:44:15 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Sun, 19 Jan 2014 18:44:15 +0100 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , Message-ID: Hi Paul, I looked into the Peris example but It is so what same like the stenosis example with a Cosine deformation. In my case it is a pipe with conical divergent. I tried to play around the variables Xm1, Ym1 and Zm1 but the mapping doesn't go well. Could you please help me with this. Thank you, Kamal On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov wrote: > Hi Paul, > > I looked at the Helix and stenosis example but they are using cosine functions to deform > > I tried to use a tangent function but it bends the whole pipe. > > I dint look at peris example . > > I will take a look at it and let you know. > > Thank you > > Kamal > > On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov wrote: > >> >> Kamal, >> >> Have you looked at the peris example? The usr file there shows how to deform >> a pipe geometry. >> >> Paul >> >> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >> Sent: Saturday, January 18, 2014 12:17 PM >> To: nek5000-users at lists.mcs.anl.gov >> Subject: Re: [Nek5000-users] Pipe with expansion >> >> Dear Paul, >> >> I tried many ways to map my straight pipe geometry but it does not seem to work properly >> >> I used something like >> >> X = X + Z * tan ( alpha ) >> Y = Y + Z* tan (alpha ) >> >> >> even that dint work. could please help me with this >> >> Thank you >> >> Kamal. >> >> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov wrote: >> >>> Hi Paul, >>> >>> Thanks paul. I tried working with the diverging mesh modification. >>> >>> I tried to use this form of equation to modify the mesh >>> >>> z = mx + b >>> z = ny + c >>> >>> x = ( z - b ) / m >>> y = (z - c) / n >>> >>> Do you think would work ? or is there any other way to input that ? >>> >>> Thanks, >>> >>> Kamal >>> >>> >>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>> Kamal, >>>> >>>> 1) To check for convergence, run your simulation for increasing polynomial orders ( lx1 in the SIZE file) and measure some consistent quantity (drag, TKE, etc). You can plot this quantity against lx1 and this should give you a good picture of how you are converging (without needing to change the physical mesh). >>>> >>>> 2) If you weren't using temperature in your simulation, you could do put the following code snippet in your userchk >>>> >>>> c------------------------------------------- >>>> integer i, ntot >>>> >>>> ntot = nx1*ny1*nz1*nelv ! total number of points in simulation (on THIS processor) >>>> >>>> do i = 1,ntot >>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + vz(i,1,1,1)**2) >>>> enddo >>>> >>>> ifto = .true. >>>> c------------------------------------------- >>>> >>>> I've assumed here that your density is unity. This computed kinetic energy point-wise and stores it in the temperature field. The part "ifto = .true." tells Nek to output the temperature field whenever it outputs a field file. You could then view this in visit just like you would the velocity field. >>>> >>>> Hope this helps! >>>> >>>> Josh >>>> >>>> >>>> >>>> >>>> >>>> On Wed, Jan 15, 2014 at 9:52 AM, wrote: >>>> Hi Paul, >>>> >>>> I will try that mapping, I created a straight pipe to do some simulations. >>>> >>>> 1) Is there a way to check my spectral convergence, so that I can do some mesh convergence study? >>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>> >>>> Thank you, >>>> Kamal >>>> >>>> >>>> >>>> >>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>> Hi Kamal, >>>> >>>> For the geometry you describe, I would apply mesh morphing >>>> to a standard straight pipe. You can create such a pipe >>>> using a subset of the mkmesh script provided in the expansion >>>> example. >>>> >>>> If your transition region is conical, then I woud make >>>> certain that the change in slope occurs at element boundaries, >>>> i.e., as in the half cross-section depicted below: >>>> >>>> _______________ >>>> /| | | >>>> / | | | >>>> /| | | | >>>> ________________/ | | | | >>>> | | | | | | | | >>>> | | | | | | | | >>>> +-----+-----+---+--+---+------+------+----> z >>>> >>>> >>>> Paul >>>> >>>> >>>> >>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>> Hi Paul, >>>> >>>> I looked at the example and it looks very helpful, but for a sudden expansion we have only two parts (i.e) the inlet pipe and the outlet pipe. Whereas in a diverging pipe we have three section (i.e,) The inlet pipe, Diverging section and the outlet pipe. >>>> >>>> >>>> Is it possible for me to create a 2D diverging section using mesh modification and revolve it around the centre axis to get a 3d diverging pipe ? >>>> >>>> >>>> or should I apply the mesh modification directly to the 3d sudden expansion pipe using usrdat2() ? >>>> >>>> Thanks, >>>> Kamal >>>> >>>> >>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>>> Hi Paul, >>>> >>>> Thanks a lot for the update. I will take a look at as soon as possible and keep you updated with it. >>>> >>>> Thank you, >>>> >>>> Kamal >>>> >>>> On Jan 14, 2014, at 9:04 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>> Kamal, >>>> >>>> I've added an example for a step-type expansion in a pipe. New example directory >>>> is nek5_svn/examples/expansion, with a README. >>>> >>>> If you want a standard diffuser, I would use mesh-morphing, as outlined in the >>>> nek primer, which can be found on this page: >>>> >>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>> >>>> I've also automated our turbulent outflow bc treatment -- one simply provides an >>>> expansion factor (typically ~ 1.5) and two persistent arrays to turb_outflow(), which >>>> is now in navier5.f. This can be useful when very strong vortices are leaving the >>>> domain, which is possible for certain diffuser flow conditions (and others). >>>> >>>> Paul >>>> ________________________________________ >>>> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf ofnek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>> Sent: Monday, January 13, 2014 3:35 AM >>>> To: nek5000-users at lists.mcs.anl.gov >>>> Subject: [Nek5000-users] Creating a Mesh >>>> >>>> Hi >>>> >>>> Can some one please help me in this because I am new to nek >>>> >>>> 1) How can I create a .rea for a specific geometry say ' A sudden >>>> expansion pipe ' or a ' Diverging pipe ' >>>> >>>> 2) What tool I should use to create that mesh. >>>> >>>> >>>> Thank you >>>> >>>> >>>> kamal >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>>> >>>> >>>> -- >>>> Josh Camp >>>> >>>> "All that is necessary for the triumph of evil is that good men do nothing" -- Edmund Burke >>>> >>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Sun Jan 19 13:45:05 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Sun, 19 Jan 2014 13:45:05 -0600 (CST) Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , Message-ID: Kamal, I would do the following in usrdat2(): n=nx1*ny1*nz1*nelt do i=1,n x=xm1(i,1,1,1) y=ym1(i,1,1,1) z=ym1(i,1,1,1) scale = 1. if (z.gt.z0) scale = smax*(z-z0/(z1-z0) if (z.gt.z1) scale = smax xm1(i,1,1,1) = scale*x ym1(i,1,1,1) = scale*y enddo Paul Make certain that z1 and z0 correspond to z values that precisely coincide with element interfaces. On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > Hi Paul, > > I looked into the Peris example but It is so what same like the stenosis example with a Cosine deformation. > > In my case it is a pipe with conical divergent. I tried to play around the variables Xm1, Ym1 and Zm1 but the mapping doesn't go well. > > Could you please help me with this. > > Thank you, > > Kamal > > > On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov wrote: > >> Hi Paul, >> >> I looked at the Helix and stenosis example but they are using cosine functions to deform >> >> I tried to use a tangent function but it bends the whole pipe. >> >> I dint look at peris example . >> >> I will take a look at it and let you know. >> >> Thank you >> >> Kamal >> >> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov wrote: >> >>> >>> Kamal, >>> >>> Have you looked at the peris example? The usr file there shows how to deform >>> a pipe geometry. >>> >>> Paul >>> >>> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>> Sent: Saturday, January 18, 2014 12:17 PM >>> To: nek5000-users at lists.mcs.anl.gov >>> Subject: Re: [Nek5000-users] Pipe with expansion >>> >>> Dear Paul, >>> >>> I tried many ways to map my straight pipe geometry but it does not seem to work properly >>> >>> I used something like >>> >>> X = X + Z * tan ( alpha ) >>> Y = Y + Z* tan (alpha ) >>> >>> >>> even that dint work. could please help me with this >>> >>> Thank you >>> >>> Kamal. >>> >>> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov wrote: >>> >>>> Hi Paul, >>>> >>>> Thanks paul. I tried working with the diverging mesh modification. >>>> >>>> I tried to use this form of equation to modify the mesh >>>> >>>> z = mx + b >>>> z = ny + c >>>> >>>> x = ( z - b ) / m >>>> y = (z - c) / n >>>> >>>> Do you think would work ? or is there any other way to input that ? >>>> >>>> Thanks, >>>> >>>> Kamal >>>> >>>> >>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>> Kamal, >>>>> >>>>> 1) To check for convergence, run your simulation for increasing polynomial orders ( lx1 in the SIZE file) and measure some consistent quantity (drag, TKE, etc). You can plot this quantity against lx1 and this should give you a good picture of how you are converging (without needing to change the physical mesh). >>>>> >>>>> 2) If you weren't using temperature in your simulation, you could do put the following code snippet in your userchk >>>>> >>>>> c------------------------------------------- >>>>> integer i, ntot >>>>> >>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in simulation (on THIS processor) >>>>> >>>>> do i = 1,ntot >>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + vz(i,1,1,1)**2) >>>>> enddo >>>>> >>>>> ifto = .true. >>>>> c------------------------------------------- >>>>> >>>>> I've assumed here that your density is unity. This computed kinetic energy point-wise and stores it in the temperature field. The part "ifto = .true." tells Nek to output the temperature field whenever it outputs a field file. You could then view this in visit just like you would the velocity field. >>>>> >>>>> Hope this helps! >>>>> >>>>> Josh >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> On Wed, Jan 15, 2014 at 9:52 AM, wrote: >>>>> Hi Paul, >>>>> >>>>> I will try that mapping, I created a straight pipe to do some simulations. >>>>> >>>>> 1) Is there a way to check my spectral convergence, so that I can do some mesh convergence study? >>>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>>> >>>>> Thank you, >>>>> Kamal >>>>> >>>>> >>>>> >>>>> >>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>> Hi Kamal, >>>>> >>>>> For the geometry you describe, I would apply mesh morphing >>>>> to a standard straight pipe. You can create such a pipe >>>>> using a subset of the mkmesh script provided in the expansion >>>>> example. >>>>> >>>>> If your transition region is conical, then I woud make >>>>> certain that the change in slope occurs at element boundaries, >>>>> i.e., as in the half cross-section depicted below: >>>>> >>>>> _______________ >>>>> /| | | >>>>> / | | | >>>>> /| | | | >>>>> ________________/ | | | | >>>>> | | | | | | | | >>>>> | | | | | | | | >>>>> +-----+-----+---+--+---+------+------+----> z >>>>> >>>>> >>>>> Paul >>>>> >>>>> >>>>> >>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>> Hi Paul, >>>>> >>>>> I looked at the example and it looks very helpful, but for a sudden expansion we have only two parts (i.e) the inlet pipe and the outlet pipe. Whereas in a diverging pipe we have three section (i.e,) The inlet pipe, Diverging section and the outlet pipe. >>>>> >>>>> >>>>> Is it possible for me to create a 2D diverging section using mesh modification and revolve it around the centre axis to get a 3d diverging pipe ? >>>>> >>>>> >>>>> or should I apply the mesh modification directly to the 3d sudden expansion pipe using usrdat2() ? >>>>> >>>>> Thanks, >>>>> Kamal >>>>> >>>>> >>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>>>> Hi Paul, >>>>> >>>>> Thanks a lot for the update. I will take a look at as soon as possible and keep you updated with it. >>>>> >>>>> Thank you, >>>>> >>>>> Kamal >>>>> >>>>> On Jan 14, 2014, at 9:04 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>> Kamal, >>>>> >>>>> I've added an example for a step-type expansion in a pipe. New example directory >>>>> is nek5_svn/examples/expansion, with a README. >>>>> >>>>> If you want a standard diffuser, I would use mesh-morphing, as outlined in the >>>>> nek primer, which can be found on this page: >>>>> >>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>> >>>>> I've also automated our turbulent outflow bc treatment -- one simply provides an >>>>> expansion factor (typically ~ 1.5) and two persistent arrays to turb_outflow(), which >>>>> is now in navier5.f. This can be useful when very strong vortices are leaving the >>>>> domain, which is possible for certain diffuser flow conditions (and others). >>>>> >>>>> Paul >>>>> ________________________________________ >>>>> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf ofnek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>> To: nek5000-users at lists.mcs.anl.gov >>>>> Subject: [Nek5000-users] Creating a Mesh >>>>> >>>>> Hi >>>>> >>>>> Can some one please help me in this because I am new to nek >>>>> >>>>> 1) How can I create a .rea for a specific geometry say ' A sudden >>>>> expansion pipe ' or a ' Diverging pipe ' >>>>> >>>>> 2) What tool I should use to create that mesh. >>>>> >>>>> >>>>> Thank you >>>>> >>>>> >>>>> kamal >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>>> >>>>> >>>>> -- >>>>> Josh Camp >>>>> >>>>> "All that is necessary for the triumph of evil is that good men do nothing" -- Edmund Burke >>>>> >>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > From nek5000-users at lists.mcs.anl.gov Sun Jan 19 17:09:11 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Mon, 20 Jan 2014 00:09:11 +0100 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , Message-ID: Hi paul, If I am not wrong, I make a mesh with three straight pipes( inlet, divergent, outlet ) connected together via n2to3 so that I know the element connectivity places of the divergent section (z0,z1) and use the section what you gave Thank you for the code Kamal On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov wrote: > > Kamal, > > I would do the following in usrdat2(): > > n=nx1*ny1*nz1*nelt > > do i=1,n > x=xm1(i,1,1,1) > y=ym1(i,1,1,1) > z=ym1(i,1,1,1) > scale = 1. > if (z.gt.z0) scale = smax*(z-z0/(z1-z0) > if (z.gt.z1) scale = smax > xm1(i,1,1,1) = scale*x > ym1(i,1,1,1) = scale*y > enddo > > Paul > > Make certain that z1 and z0 correspond to z values > that precisely coincide with element interfaces. > > > On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > >> Hi Paul, >> >> I looked into the Peris example but It is so what same like the stenosis example with a Cosine deformation. >> >> In my case it is a pipe with conical divergent. I tried to play around the variables Xm1, Ym1 and Zm1 but the mapping doesn't go well. >> >> Could you please help me with this. >> >> Thank you, >> >> Kamal >> >> >> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov wrote: >> >>> Hi Paul, >>> >>> I looked at the Helix and stenosis example but they are using cosine functions to deform >>> >>> I tried to use a tangent function but it bends the whole pipe. >>> >>> I dint look at peris example . >>> >>> I will take a look at it and let you know. >>> >>> Thank you >>> >>> Kamal >>> >>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov wrote: >>> >>>> >>>> Kamal, >>>> >>>> Have you looked at the peris example? The usr file there shows how to deform >>>> a pipe geometry. >>>> >>>> Paul >>>> >>>> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>> Sent: Saturday, January 18, 2014 12:17 PM >>>> To: nek5000-users at lists.mcs.anl.gov >>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>> >>>> Dear Paul, >>>> >>>> I tried many ways to map my straight pipe geometry but it does not seem to work properly >>>> >>>> I used something like >>>> >>>> X = X + Z * tan ( alpha ) >>>> Y = Y + Z* tan (alpha ) >>>> >>>> >>>> even that dint work. could please help me with this >>>> >>>> Thank you >>>> >>>> Kamal. >>>> >>>> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> Hi Paul, >>>>> >>>>> Thanks paul. I tried working with the diverging mesh modification. >>>>> >>>>> I tried to use this form of equation to modify the mesh >>>>> >>>>> z = mx + b >>>>> z = ny + c >>>>> >>>>> x = ( z - b ) / m >>>>> y = (z - c) / n >>>>> >>>>> Do you think would work ? or is there any other way to input that ? >>>>> >>>>> Thanks, >>>>> >>>>> Kamal >>>>> >>>>> >>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>> Kamal, >>>>>> >>>>>> 1) To check for convergence, run your simulation for increasing polynomial orders ( lx1 in the SIZE file) and measure some consistent quantity (drag, TKE, etc). You can plot this quantity against lx1 and this should give you a good picture of how you are converging (without needing to change the physical mesh). >>>>>> >>>>>> 2) If you weren't using temperature in your simulation, you could do put the following code snippet in your userchk >>>>>> >>>>>> c------------------------------------------- >>>>>> integer i, ntot >>>>>> >>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in simulation (on THIS processor) >>>>>> >>>>>> do i = 1,ntot >>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + vz(i,1,1,1)**2) >>>>>> enddo >>>>>> >>>>>> ifto = .true. >>>>>> c------------------------------------------- >>>>>> >>>>>> I've assumed here that your density is unity. This computed kinetic energy point-wise and stores it in the temperature field. The part "ifto = .true." tells Nek to output the temperature field whenever it outputs a field file. You could then view this in visit just like you would the velocity field. >>>>>> >>>>>> Hope this helps! >>>>>> >>>>>> Josh >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> On Wed, Jan 15, 2014 at 9:52 AM, wrote: >>>>>> Hi Paul, >>>>>> >>>>>> I will try that mapping, I created a straight pipe to do some simulations. >>>>>> >>>>>> 1) Is there a way to check my spectral convergence, so that I can do some mesh convergence study? >>>>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>>>> >>>>>> Thank you, >>>>>> Kamal >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>> Hi Kamal, >>>>>> >>>>>> For the geometry you describe, I would apply mesh morphing >>>>>> to a standard straight pipe. You can create such a pipe >>>>>> using a subset of the mkmesh script provided in the expansion >>>>>> example. >>>>>> >>>>>> If your transition region is conical, then I woud make >>>>>> certain that the change in slope occurs at element boundaries, >>>>>> i.e., as in the half cross-section depicted below: >>>>>> >>>>>> _______________ >>>>>> /| | | >>>>>> / | | | >>>>>> /| | | | >>>>>> ________________/ | | | | >>>>>> | | | | | | | | >>>>>> | | | | | | | | >>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>> >>>>>> >>>>>> Paul >>>>>> >>>>>> >>>>>> >>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>> Hi Paul, >>>>>> >>>>>> I looked at the example and it looks very helpful, but for a sudden expansion we have only two parts (i.e) the inlet pipe and the outlet pipe. Whereas in a diverging pipe we have three section (i.e,) The inlet pipe, Diverging section and the outlet pipe. >>>>>> >>>>>> >>>>>> Is it possible for me to create a 2D diverging section using mesh modification and revolve it around the centre axis to get a 3d diverging pipe ? >>>>>> >>>>>> >>>>>> or should I apply the mesh modification directly to the 3d sudden expansion pipe using usrdat2() ? >>>>>> >>>>>> Thanks, >>>>>> Kamal >>>>>> >>>>>> >>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> Hi Paul, >>>>>> >>>>>> Thanks a lot for the update. I will take a look at as soon as possible and keep you updated with it. >>>>>> >>>>>> Thank you, >>>>>> >>>>>> Kamal >>>>>> >>>>>> On Jan 14, 2014, at 9:04 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>> Kamal, >>>>>> >>>>>> I've added an example for a step-type expansion in a pipe. New example directory >>>>>> is nek5_svn/examples/expansion, with a README. >>>>>> >>>>>> If you want a standard diffuser, I would use mesh-morphing, as outlined in the >>>>>> nek primer, which can be found on this page: >>>>>> >>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>> >>>>>> I've also automated our turbulent outflow bc treatment -- one simply provides an >>>>>> expansion factor (typically ~ 1.5) and two persistent arrays to turb_outflow(), which >>>>>> is now in navier5.f. This can be useful when very strong vortices are leaving the >>>>>> domain, which is possible for certain diffuser flow conditions (and others). >>>>>> >>>>>> Paul >>>>>> ________________________________________ >>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf ofnek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>> >>>>>> Hi >>>>>> >>>>>> Can some one please help me in this because I am new to nek >>>>>> >>>>>> 1) How can I create a .rea for a specific geometry say ' A sudden >>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>> >>>>>> 2) What tool I should use to create that mesh. >>>>>> >>>>>> >>>>>> Thank you >>>>>> >>>>>> >>>>>> kamal >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> Josh Camp >>>>>> >>>>>> "All that is necessary for the triumph of evil is that good men do nothing" -- Edmund Burke >>>>>> >>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users From nek5000-users at lists.mcs.anl.gov Sun Jan 19 19:00:52 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Mon, 20 Jan 2014 02:00:52 +0100 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , Message-ID: Hi paul, The code works fine, but there should be a small change thats has to be done if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) if (z.gt.z1) scale = smax This creates a perfect diverging pipe. Thanks for the help paul. Kamal On Jan 20, 2014, at 12:09 AM, nek5000-users at lists.mcs.anl.gov wrote: > Hi paul, > > If I am not wrong, > I make a mesh with three straight pipes( inlet, divergent, outlet ) connected together via n2to3 so that I know the element connectivity places of the divergent section (z0,z1) and use the section what you gave > > Thank you for the code > > Kamal > > On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov wrote: > >> >> Kamal, >> >> I would do the following in usrdat2(): >> >> n=nx1*ny1*nz1*nelt >> >> do i=1,n >> x=xm1(i,1,1,1) >> y=ym1(i,1,1,1) >> z=ym1(i,1,1,1) >> scale = 1. >> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >> if (z.gt.z1) scale = smax >> xm1(i,1,1,1) = scale*x >> ym1(i,1,1,1) = scale*y >> enddo >> >> Paul >> >> Make certain that z1 and z0 correspond to z values >> that precisely coincide with element interfaces. >> >> >> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >> >>> Hi Paul, >>> >>> I looked into the Peris example but It is so what same like the stenosis example with a Cosine deformation. >>> >>> In my case it is a pipe with conical divergent. I tried to play around the variables Xm1, Ym1 and Zm1 but the mapping doesn't go well. >>> >>> Could you please help me with this. >>> >>> Thank you, >>> >>> Kamal >>> >>> >>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov wrote: >>> >>>> Hi Paul, >>>> >>>> I looked at the Helix and stenosis example but they are using cosine functions to deform >>>> >>>> I tried to use a tangent function but it bends the whole pipe. >>>> >>>> I dint look at peris example . >>>> >>>> I will take a look at it and let you know. >>>> >>>> Thank you >>>> >>>> Kamal >>>> >>>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> >>>>> Kamal, >>>>> >>>>> Have you looked at the peris example? The usr file there shows how to deform >>>>> a pipe geometry. >>>>> >>>>> Paul >>>>> >>>>> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>> To: nek5000-users at lists.mcs.anl.gov >>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>> >>>>> Dear Paul, >>>>> >>>>> I tried many ways to map my straight pipe geometry but it does not seem to work properly >>>>> >>>>> I used something like >>>>> >>>>> X = X + Z * tan ( alpha ) >>>>> Y = Y + Z* tan (alpha ) >>>>> >>>>> >>>>> even that dint work. could please help me with this >>>>> >>>>> Thank you >>>>> >>>>> Kamal. >>>>> >>>>> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>>> Hi Paul, >>>>>> >>>>>> Thanks paul. I tried working with the diverging mesh modification. >>>>>> >>>>>> I tried to use this form of equation to modify the mesh >>>>>> >>>>>> z = mx + b >>>>>> z = ny + c >>>>>> >>>>>> x = ( z - b ) / m >>>>>> y = (z - c) / n >>>>>> >>>>>> Do you think would work ? or is there any other way to input that ? >>>>>> >>>>>> Thanks, >>>>>> >>>>>> Kamal >>>>>> >>>>>> >>>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>>> Kamal, >>>>>>> >>>>>>> 1) To check for convergence, run your simulation for increasing polynomial orders ( lx1 in the SIZE file) and measure some consistent quantity (drag, TKE, etc). You can plot this quantity against lx1 and this should give you a good picture of how you are converging (without needing to change the physical mesh). >>>>>>> >>>>>>> 2) If you weren't using temperature in your simulation, you could do put the following code snippet in your userchk >>>>>>> >>>>>>> c------------------------------------------- >>>>>>> integer i, ntot >>>>>>> >>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in simulation (on THIS processor) >>>>>>> >>>>>>> do i = 1,ntot >>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + vz(i,1,1,1)**2) >>>>>>> enddo >>>>>>> >>>>>>> ifto = .true. >>>>>>> c------------------------------------------- >>>>>>> >>>>>>> I've assumed here that your density is unity. This computed kinetic energy point-wise and stores it in the temperature field. The part "ifto = .true." tells Nek to output the temperature field whenever it outputs a field file. You could then view this in visit just like you would the velocity field. >>>>>>> >>>>>>> Hope this helps! >>>>>>> >>>>>>> Josh >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, wrote: >>>>>>> Hi Paul, >>>>>>> >>>>>>> I will try that mapping, I created a straight pipe to do some simulations. >>>>>>> >>>>>>> 1) Is there a way to check my spectral convergence, so that I can do some mesh convergence study? >>>>>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>>>>> >>>>>>> Thank you, >>>>>>> Kamal >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>> Hi Kamal, >>>>>>> >>>>>>> For the geometry you describe, I would apply mesh morphing >>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>> using a subset of the mkmesh script provided in the expansion >>>>>>> example. >>>>>>> >>>>>>> If your transition region is conical, then I woud make >>>>>>> certain that the change in slope occurs at element boundaries, >>>>>>> i.e., as in the half cross-section depicted below: >>>>>>> >>>>>>> _______________ >>>>>>> /| | | >>>>>>> / | | | >>>>>>> /| | | | >>>>>>> ________________/ | | | | >>>>>>> | | | | | | | | >>>>>>> | | | | | | | | >>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>> >>>>>>> >>>>>>> Paul >>>>>>> >>>>>>> >>>>>>> >>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>> Hi Paul, >>>>>>> >>>>>>> I looked at the example and it looks very helpful, but for a sudden expansion we have only two parts (i.e) the inlet pipe and the outlet pipe. Whereas in a diverging pipe we have three section (i.e,) The inlet pipe, Diverging section and the outlet pipe. >>>>>>> >>>>>>> >>>>>>> Is it possible for me to create a 2D diverging section using mesh modification and revolve it around the centre axis to get a 3d diverging pipe ? >>>>>>> >>>>>>> >>>>>>> or should I apply the mesh modification directly to the 3d sudden expansion pipe using usrdat2() ? >>>>>>> >>>>>>> Thanks, >>>>>>> Kamal >>>>>>> >>>>>>> >>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> Hi Paul, >>>>>>> >>>>>>> Thanks a lot for the update. I will take a look at as soon as possible and keep you updated with it. >>>>>>> >>>>>>> Thank you, >>>>>>> >>>>>>> Kamal >>>>>>> >>>>>>> On Jan 14, 2014, at 9:04 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>> Kamal, >>>>>>> >>>>>>> I've added an example for a step-type expansion in a pipe. New example directory >>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>> >>>>>>> If you want a standard diffuser, I would use mesh-morphing, as outlined in the >>>>>>> nek primer, which can be found on this page: >>>>>>> >>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>> >>>>>>> I've also automated our turbulent outflow bc treatment -- one simply provides an >>>>>>> expansion factor (typically ~ 1.5) and two persistent arrays to turb_outflow(), which >>>>>>> is now in navier5.f. This can be useful when very strong vortices are leaving the >>>>>>> domain, which is possible for certain diffuser flow conditions (and others). >>>>>>> >>>>>>> Paul >>>>>>> ________________________________________ >>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf ofnek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>> >>>>>>> Hi >>>>>>> >>>>>>> Can some one please help me in this because I am new to nek >>>>>>> >>>>>>> 1) How can I create a .rea for a specific geometry say ' A sudden >>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>> >>>>>>> 2) What tool I should use to create that mesh. >>>>>>> >>>>>>> >>>>>>> Thank you >>>>>>> >>>>>>> >>>>>>> kamal >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> >>>>>>> >>>>>>> -- >>>>>>> Josh Camp >>>>>>> >>>>>>> "All that is necessary for the triumph of evil is that good men do nothing" -- Edmund Burke >>>>>>> >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users From nek5000-users at lists.mcs.anl.gov Sun Jan 19 22:41:49 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Sun, 19 Jan 2014 22:41:49 -0600 (CST) Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , Message-ID: Kamal, Looks good. I'm guessing that one further refinement would be: if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) if (z.gt.z1) scale = smax which would yield scale = 1 when z=z0 scale = smax when z >= z1 Paul On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > Hi paul, > > The code works fine, but there should be a small change thats has to be done > > > if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) > if (z.gt.z1) scale = smax > > This creates a perfect diverging pipe. > > Thanks for the help paul. > > Kamal > > On Jan 20, 2014, at 12:09 AM, nek5000-users at lists.mcs.anl.gov wrote: > >> Hi paul, >> >> If I am not wrong, >> I make a mesh with three straight pipes( inlet, divergent, outlet ) connected together via n2to3 so that I know the element connectivity places of the divergent section (z0,z1) and use the section what you gave >> >> Thank you for the code >> >> Kamal >> >> On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov wrote: >> >>> >>> Kamal, >>> >>> I would do the following in usrdat2(): >>> >>> n=nx1*ny1*nz1*nelt >>> >>> do i=1,n >>> x=xm1(i,1,1,1) >>> y=ym1(i,1,1,1) >>> z=ym1(i,1,1,1) >>> scale = 1. >>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>> if (z.gt.z1) scale = smax >>> xm1(i,1,1,1) = scale*x >>> ym1(i,1,1,1) = scale*y >>> enddo >>> >>> Paul >>> >>> Make certain that z1 and z0 correspond to z values >>> that precisely coincide with element interfaces. >>> >>> >>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>> >>>> Hi Paul, >>>> >>>> I looked into the Peris example but It is so what same like the stenosis example with a Cosine deformation. >>>> >>>> In my case it is a pipe with conical divergent. I tried to play around the variables Xm1, Ym1 and Zm1 but the mapping doesn't go well. >>>> >>>> Could you please help me with this. >>>> >>>> Thank you, >>>> >>>> Kamal >>>> >>>> >>>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> Hi Paul, >>>>> >>>>> I looked at the Helix and stenosis example but they are using cosine functions to deform >>>>> >>>>> I tried to use a tangent function but it bends the whole pipe. >>>>> >>>>> I dint look at peris example . >>>>> >>>>> I will take a look at it and let you know. >>>>> >>>>> Thank you >>>>> >>>>> Kamal >>>>> >>>>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>>> >>>>>> Kamal, >>>>>> >>>>>> Have you looked at the peris example? The usr file there shows how to deform >>>>>> a pipe geometry. >>>>>> >>>>>> Paul >>>>>> >>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>> >>>>>> Dear Paul, >>>>>> >>>>>> I tried many ways to map my straight pipe geometry but it does not seem to work properly >>>>>> >>>>>> I used something like >>>>>> >>>>>> X = X + Z * tan ( alpha ) >>>>>> Y = Y + Z* tan (alpha ) >>>>>> >>>>>> >>>>>> even that dint work. could please help me with this >>>>>> >>>>>> Thank you >>>>>> >>>>>> Kamal. >>>>>> >>>>>> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>>> Hi Paul, >>>>>>> >>>>>>> Thanks paul. I tried working with the diverging mesh modification. >>>>>>> >>>>>>> I tried to use this form of equation to modify the mesh >>>>>>> >>>>>>> z = mx + b >>>>>>> z = ny + c >>>>>>> >>>>>>> x = ( z - b ) / m >>>>>>> y = (z - c) / n >>>>>>> >>>>>>> Do you think would work ? or is there any other way to input that ? >>>>>>> >>>>>>> Thanks, >>>>>>> >>>>>>> Kamal >>>>>>> >>>>>>> >>>>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>>>> Kamal, >>>>>>>> >>>>>>>> 1) To check for convergence, run your simulation for increasing polynomial orders ( lx1 in the SIZE file) and measure some consistent quantity (drag, TKE, etc). You can plot this quantity against lx1 and this should give you a good picture of how you are converging (without needing to change the physical mesh). >>>>>>>> >>>>>>>> 2) If you weren't using temperature in your simulation, you could do put the following code snippet in your userchk >>>>>>>> >>>>>>>> c------------------------------------------- >>>>>>>> integer i, ntot >>>>>>>> >>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in simulation (on THIS processor) >>>>>>>> >>>>>>>> do i = 1,ntot >>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + vz(i,1,1,1)**2) >>>>>>>> enddo >>>>>>>> >>>>>>>> ifto = .true. >>>>>>>> c------------------------------------------- >>>>>>>> >>>>>>>> I've assumed here that your density is unity. This computed kinetic energy point-wise and stores it in the temperature field. The part "ifto = .true." tells Nek to output the temperature field whenever it outputs a field file. You could then view this in visit just like you would the velocity field. >>>>>>>> >>>>>>>> Hope this helps! >>>>>>>> >>>>>>>> Josh >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, wrote: >>>>>>>> Hi Paul, >>>>>>>> >>>>>>>> I will try that mapping, I created a straight pipe to do some simulations. >>>>>>>> >>>>>>>> 1) Is there a way to check my spectral convergence, so that I can do some mesh convergence study? >>>>>>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>>>>>> >>>>>>>> Thank you, >>>>>>>> Kamal >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> >>>>>>>> Hi Kamal, >>>>>>>> >>>>>>>> For the geometry you describe, I would apply mesh morphing >>>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>>> using a subset of the mkmesh script provided in the expansion >>>>>>>> example. >>>>>>>> >>>>>>>> If your transition region is conical, then I woud make >>>>>>>> certain that the change in slope occurs at element boundaries, >>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>> >>>>>>>> _______________ >>>>>>>> /| | | >>>>>>>> / | | | >>>>>>>> /| | | | >>>>>>>> ________________/ | | | | >>>>>>>> | | | | | | | | >>>>>>>> | | | | | | | | >>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>> >>>>>>>> >>>>>>>> Paul >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> >>>>>>>> Hi Paul, >>>>>>>> >>>>>>>> I looked at the example and it looks very helpful, but for a sudden expansion we have only two parts (i.e) the inlet pipe and the outlet pipe. Whereas in a diverging pipe we have three section (i.e,) The inlet pipe, Diverging section and the outlet pipe. >>>>>>>> >>>>>>>> >>>>>>>> Is it possible for me to create a 2D diverging section using mesh modification and revolve it around the centre axis to get a 3d diverging pipe ? >>>>>>>> >>>>>>>> >>>>>>>> or should I apply the mesh modification directly to the 3d sudden expansion pipe using usrdat2() ? >>>>>>>> >>>>>>>> Thanks, >>>>>>>> Kamal >>>>>>>> >>>>>>>> >>>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> Hi Paul, >>>>>>>> >>>>>>>> Thanks a lot for the update. I will take a look at as soon as possible and keep you updated with it. >>>>>>>> >>>>>>>> Thank you, >>>>>>>> >>>>>>>> Kamal >>>>>>>> >>>>>>>> On Jan 14, 2014, at 9:04 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> >>>>>>>> Kamal, >>>>>>>> >>>>>>>> I've added an example for a step-type expansion in a pipe. New example directory >>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>> >>>>>>>> If you want a standard diffuser, I would use mesh-morphing, as outlined in the >>>>>>>> nek primer, which can be found on this page: >>>>>>>> >>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>> >>>>>>>> I've also automated our turbulent outflow bc treatment -- one simply provides an >>>>>>>> expansion factor (typically ~ 1.5) and two persistent arrays to turb_outflow(), which >>>>>>>> is now in navier5.f. This can be useful when very strong vortices are leaving the >>>>>>>> domain, which is possible for certain diffuser flow conditions (and others). >>>>>>>> >>>>>>>> Paul >>>>>>>> ________________________________________ >>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf ofnek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>> >>>>>>>> Hi >>>>>>>> >>>>>>>> Can some one please help me in this because I am new to nek >>>>>>>> >>>>>>>> 1) How can I create a .rea for a specific geometry say ' A sudden >>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>> >>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>> >>>>>>>> >>>>>>>> Thank you >>>>>>>> >>>>>>>> >>>>>>>> kamal >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> -- >>>>>>>> Josh Camp >>>>>>>> >>>>>>>> "All that is necessary for the triumph of evil is that good men do nothing" -- Edmund Burke >>>>>>>> >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > From nek5000-users at lists.mcs.anl.gov Mon Jan 20 02:51:35 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Mon, 20 Jan 2014 09:51:35 +0100 Subject: [Nek5000-users] Load_fld() without restart In-Reply-To: References: Message-ID: Hi Josh, Thank you for your answer. We had already considered using this approach but we have a few queries. We would like to load a .fld file at each time step, which means the process might become very costly. Do you have any idea of the cost (in time) of such a method? Also, what becomes of the variables calculated during the previous time steps? Thanks again, Holly Le 17/01/2014 14:21, nek5000-users at lists.mcs.anl.gov a ?crit : > Hi Holly, > > If you wanted to load a .fld file without copying over your variables, > you could do something like > > ! Create temporary storage > real tmp1(lx1*ly1*lz1*lelv), tmp2(lx1*ly1*lz1*lelv), ... > > ! Copy simulation fields to temporary variables > call copy(tmp1,vx,nx1*ny1*nz1*nelv) > ... > > ! Load field file and do whatever work you want to do with it > > ! Copy simulation fields back to nek variables > call copy(vx,tmp1,nx1*ny1*nz1*nelv) > > > You should be able to use some of the Nek scratch arrays to store your > temporary variables (instead of taking up more memory with the > explicit declaration), but I'm not sure at the moment which scratch > arrays load_fld() uses. > > - Josh > > > > On Fri, Jan 17, 2014 at 4:56 AM, > wrote: > > Hi Neks ! > > Is there a way to load a .fld file during a simulation (in the > same way load_fld() does) but without doing a complete restart of > all the variables ? > > Thanks for any help ! > > Holly > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > > > > -- > Josh Camp > > "All that is necessary for the triumph of evil is that good men do > nothing" -- Edmund Burke > > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Mon Jan 20 11:33:53 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Mon, 20 Jan 2014 11:33:53 -0600 Subject: [Nek5000-users] Load_fld() without restart In-Reply-To: References: Message-ID: Hi Holly, I'm not quite sure how to estimate how much time is needed to load the .fld files, it would certainly depend on how many processors you are using, whether you are using MPI_IO, etc.. (maybe the main developers could give some sort of leading order complexity here?) As for the variables, the main variables (vx, vy, vz, pr, t) are overwritten each time step, although I think there are some lag arrays available (such as vxlag). However, I'm not familiar with how these are used, so you may want to do some digging. Josh On Mon, Jan 20, 2014 at 2:51 AM, wrote: > Hi Josh, > > Thank you for your answer. We had already considered using this approach > but we have a few queries. We would like to load a .fld file at each time > step, which means the process might become very costly. Do you have any > idea of the cost (in time) of such a method? Also, what becomes of the > variables calculated during the previous time steps? > > Thanks again, > > Holly > > Le 17/01/2014 14:21, nek5000-users at lists.mcs.anl.gov a ?crit : > > Hi Holly, > > If you wanted to load a .fld file without copying over your variables, > you could do something like > > ! Create temporary storage > real tmp1(lx1*ly1*lz1*lelv), tmp2(lx1*ly1*lz1*lelv), ... > > ! Copy simulation fields to temporary variables > call copy(tmp1,vx,nx1*ny1*nz1*nelv) > ... > > ! Load field file and do whatever work you want to do with it > > ! Copy simulation fields back to nek variables > call copy(vx,tmp1,nx1*ny1*nz1*nelv) > > > You should be able to use some of the Nek scratch arrays to store your > temporary variables (instead of taking up more memory with the explicit > declaration), but I'm not sure at the moment which scratch arrays > load_fld() uses. > > - Josh > > > > On Fri, Jan 17, 2014 at 4:56 AM, wrote: > >> Hi Neks ! >> >> Is there a way to load a .fld file during a simulation (in the same way >> load_fld() does) but without doing a complete restart of all the variables ? >> >> Thanks for any help ! >> >> Holly >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> > > > > -- > Josh Camp > > "All that is necessary for the triumph of evil is that good men do > nothing" -- Edmund Burke > > > _______________________________________________ > Nek5000-users mailing listNek5000-users at lists.mcs.anl.govhttps://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > -- Josh Camp "All that is necessary for the triumph of evil is that good men do nothing" -- Edmund Burke -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Mon Jan 20 14:33:34 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Mon, 20 Jan 2014 14:33:34 -0600 (CST) Subject: [Nek5000-users] Load_fld() without restart In-Reply-To: References: Message-ID: Hi Holly, For certain, you would want to use the .f00000 format for this, with MPI-IO turned on via the flag in makenek. What you propose would definitely be i/o intensive and I expect more time would be spent reading than computing. Are you certain you need to re-load at every timestep? Paul On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > Hi Holly, > > I'm not quite sure how to estimate how much time is needed to load the .fld > files, it would certainly depend on how many processors you are using, > whether you are using MPI_IO, etc.. (maybe the main developers could give > some sort of leading order complexity here?) > > As for the variables, the main variables (vx, vy, vz, pr, t) are > overwritten each time step, although I think there are some lag arrays > available (such as vxlag). However, I'm not familiar with how these are > used, so you may want to do some digging. > > Josh > > > On Mon, Jan 20, 2014 at 2:51 AM, wrote: > >> Hi Josh, >> >> Thank you for your answer. We had already considered using this approach >> but we have a few queries. We would like to load a .fld file at each time >> step, which means the process might become very costly. Do you have any >> idea of the cost (in time) of such a method? Also, what becomes of the >> variables calculated during the previous time steps? >> >> Thanks again, >> >> Holly >> >> Le 17/01/2014 14:21, nek5000-users at lists.mcs.anl.gov a ?crit : >> >> Hi Holly, >> >> If you wanted to load a .fld file without copying over your variables, >> you could do something like >> >> ! Create temporary storage >> real tmp1(lx1*ly1*lz1*lelv), tmp2(lx1*ly1*lz1*lelv), ... >> >> ! Copy simulation fields to temporary variables >> call copy(tmp1,vx,nx1*ny1*nz1*nelv) >> ... >> >> ! Load field file and do whatever work you want to do with it >> >> ! Copy simulation fields back to nek variables >> call copy(vx,tmp1,nx1*ny1*nz1*nelv) >> >> >> You should be able to use some of the Nek scratch arrays to store your >> temporary variables (instead of taking up more memory with the explicit >> declaration), but I'm not sure at the moment which scratch arrays >> load_fld() uses. >> >> - Josh >> >> >> >> On Fri, Jan 17, 2014 at 4:56 AM, wrote: >> >>> Hi Neks ! >>> >>> Is there a way to load a .fld file during a simulation (in the same way >>> load_fld() does) but without doing a complete restart of all the variables ? >>> >>> Thanks for any help ! >>> >>> Holly >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >> >> >> >> -- >> Josh Camp >> >> "All that is necessary for the triumph of evil is that good men do >> nothing" -- Edmund Burke >> >> >> _______________________________________________ >> Nek5000-users mailing listNek5000-users at lists.mcs.anl.govhttps://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> > > > -- > Josh Camp > > "All that is necessary for the triumph of evil is that good men do nothing" > -- Edmund Burke > From nek5000-users at lists.mcs.anl.gov Mon Jan 20 14:36:30 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Mon, 20 Jan 2014 21:36:30 +0100 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , Message-ID: Hi Paul, Thanks and that helped. Where can I find the variables like Turbulent KE , shear stress on the wall. ? Do i have to activate some parameters for calculating them ? If I had to plot them. Thanks, Kamal On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov wrote: > > Kamal, > > Looks good. > > I'm guessing that one further refinement would be: > > if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) > if (z.gt.z1) scale = smax > > which would yield > > scale = 1 when z=z0 > scale = smax when z >= z1 > > Paul > > > > On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > >> Hi paul, >> >> The code works fine, but there should be a small change thats has to be done >> >> >> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >> if (z.gt.z1) scale = smax >> >> This creates a perfect diverging pipe. >> >> Thanks for the help paul. >> >> Kamal >> >> On Jan 20, 2014, at 12:09 AM, nek5000-users at lists.mcs.anl.gov wrote: >> >>> Hi paul, >>> >>> If I am not wrong, >>> I make a mesh with three straight pipes( inlet, divergent, outlet ) connected together via n2to3 so that I know the element connectivity places of the divergent section (z0,z1) and use the section what you gave >>> >>> Thank you for the code >>> >>> Kamal >>> >>> On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov wrote: >>> >>>> >>>> Kamal, >>>> >>>> I would do the following in usrdat2(): >>>> >>>> n=nx1*ny1*nz1*nelt >>>> >>>> do i=1,n >>>> x=xm1(i,1,1,1) >>>> y=ym1(i,1,1,1) >>>> z=ym1(i,1,1,1) >>>> scale = 1. >>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>> if (z.gt.z1) scale = smax >>>> xm1(i,1,1,1) = scale*x >>>> ym1(i,1,1,1) = scale*y >>>> enddo >>>> >>>> Paul >>>> >>>> Make certain that z1 and z0 correspond to z values >>>> that precisely coincide with element interfaces. >>>> >>>> >>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> Hi Paul, >>>>> >>>>> I looked into the Peris example but It is so what same like the stenosis example with a Cosine deformation. >>>>> >>>>> In my case it is a pipe with conical divergent. I tried to play around the variables Xm1, Ym1 and Zm1 but the mapping doesn't go well. >>>>> >>>>> Could you please help me with this. >>>>> >>>>> Thank you, >>>>> >>>>> Kamal >>>>> >>>>> >>>>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>>> Hi Paul, >>>>>> >>>>>> I looked at the Helix and stenosis example but they are using cosine functions to deform >>>>>> >>>>>> I tried to use a tangent function but it bends the whole pipe. >>>>>> >>>>>> I dint look at peris example . >>>>>> >>>>>> I will take a look at it and let you know. >>>>>> >>>>>> Thank you >>>>>> >>>>>> Kamal >>>>>> >>>>>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>>> >>>>>>> Kamal, >>>>>>> >>>>>>> Have you looked at the peris example? The usr file there shows how to deform >>>>>>> a pipe geometry. >>>>>>> >>>>>>> Paul >>>>>>> >>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>> >>>>>>> Dear Paul, >>>>>>> >>>>>>> I tried many ways to map my straight pipe geometry but it does not seem to work properly >>>>>>> >>>>>>> I used something like >>>>>>> >>>>>>> X = X + Z * tan ( alpha ) >>>>>>> Y = Y + Z* tan (alpha ) >>>>>>> >>>>>>> >>>>>>> even that dint work. could please help me with this >>>>>>> >>>>>>> Thank you >>>>>>> >>>>>>> Kamal. >>>>>>> >>>>>>> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>>> Hi Paul, >>>>>>>> >>>>>>>> Thanks paul. I tried working with the diverging mesh modification. >>>>>>>> >>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>> >>>>>>>> z = mx + b >>>>>>>> z = ny + c >>>>>>>> >>>>>>>> x = ( z - b ) / m >>>>>>>> y = (z - c) / n >>>>>>>> >>>>>>>> Do you think would work ? or is there any other way to input that ? >>>>>>>> >>>>>>>> Thanks, >>>>>>>> >>>>>>>> Kamal >>>>>>>> >>>>>>>> >>>>>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>> Kamal, >>>>>>>>> >>>>>>>>> 1) To check for convergence, run your simulation for increasing polynomial orders ( lx1 in the SIZE file) and measure some consistent quantity (drag, TKE, etc). You can plot this quantity against lx1 and this should give you a good picture of how you are converging (without needing to change the physical mesh). >>>>>>>>> >>>>>>>>> 2) If you weren't using temperature in your simulation, you could do put the following code snippet in your userchk >>>>>>>>> >>>>>>>>> c------------------------------------------- >>>>>>>>> integer i, ntot >>>>>>>>> >>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in simulation (on THIS processor) >>>>>>>>> >>>>>>>>> do i = 1,ntot >>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + vz(i,1,1,1)**2) >>>>>>>>> enddo >>>>>>>>> >>>>>>>>> ifto = .true. >>>>>>>>> c------------------------------------------- >>>>>>>>> >>>>>>>>> I've assumed here that your density is unity. This computed kinetic energy point-wise and stores it in the temperature field. The part "ifto = .true." tells Nek to output the temperature field whenever it outputs a field file. You could then view this in visit just like you would the velocity field. >>>>>>>>> >>>>>>>>> Hope this helps! >>>>>>>>> >>>>>>>>> Josh >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, wrote: >>>>>>>>> Hi Paul, >>>>>>>>> >>>>>>>>> I will try that mapping, I created a straight pipe to do some simulations. >>>>>>>>> >>>>>>>>> 1) Is there a way to check my spectral convergence, so that I can do some mesh convergence study? >>>>>>>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>>>>>>> >>>>>>>>> Thank you, >>>>>>>>> Kamal >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>> >>>>>>>>> Hi Kamal, >>>>>>>>> >>>>>>>>> For the geometry you describe, I would apply mesh morphing >>>>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>>>> using a subset of the mkmesh script provided in the expansion >>>>>>>>> example. >>>>>>>>> >>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>> certain that the change in slope occurs at element boundaries, >>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>> >>>>>>>>> _______________ >>>>>>>>> /| | | >>>>>>>>> / | | | >>>>>>>>> /| | | | >>>>>>>>> ________________/ | | | | >>>>>>>>> | | | | | | | | >>>>>>>>> | | | | | | | | >>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>> >>>>>>>>> >>>>>>>>> Paul >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>> >>>>>>>>> Hi Paul, >>>>>>>>> >>>>>>>>> I looked at the example and it looks very helpful, but for a sudden expansion we have only two parts (i.e) the inlet pipe and the outlet pipe. Whereas in a diverging pipe we have three section (i.e,) The inlet pipe, Diverging section and the outlet pipe. >>>>>>>>> >>>>>>>>> >>>>>>>>> Is it possible for me to create a 2D diverging section using mesh modification and revolve it around the centre axis to get a 3d diverging pipe ? >>>>>>>>> >>>>>>>>> >>>>>>>>> or should I apply the mesh modification directly to the 3d sudden expansion pipe using usrdat2() ? >>>>>>>>> >>>>>>>>> Thanks, >>>>>>>>> Kamal >>>>>>>>> >>>>>>>>> >>>>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>> Hi Paul, >>>>>>>>> >>>>>>>>> Thanks a lot for the update. I will take a look at as soon as possible and keep you updated with it. >>>>>>>>> >>>>>>>>> Thank you, >>>>>>>>> >>>>>>>>> Kamal >>>>>>>>> >>>>>>>>> On Jan 14, 2014, at 9:04 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>> >>>>>>>>> Kamal, >>>>>>>>> >>>>>>>>> I've added an example for a step-type expansion in a pipe. New example directory >>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>> >>>>>>>>> If you want a standard diffuser, I would use mesh-morphing, as outlined in the >>>>>>>>> nek primer, which can be found on this page: >>>>>>>>> >>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>> >>>>>>>>> I've also automated our turbulent outflow bc treatment -- one simply provides an >>>>>>>>> expansion factor (typically ~ 1.5) and two persistent arrays to turb_outflow(), which >>>>>>>>> is now in navier5.f. This can be useful when very strong vortices are leaving the >>>>>>>>> domain, which is possible for certain diffuser flow conditions (and others). >>>>>>>>> >>>>>>>>> Paul >>>>>>>>> ________________________________________ >>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf ofnek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>> >>>>>>>>> Hi >>>>>>>>> >>>>>>>>> Can some one please help me in this because I am new to nek >>>>>>>>> >>>>>>>>> 1) How can I create a .rea for a specific geometry say ' A sudden >>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>> >>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>> >>>>>>>>> >>>>>>>>> Thank you >>>>>>>>> >>>>>>>>> >>>>>>>>> kamal >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> -- >>>>>>>>> Josh Camp >>>>>>>>> >>>>>>>>> "All that is necessary for the triumph of evil is that good men do nothing" -- Edmund Burke >>>>>>>>> >>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users From nek5000-users at lists.mcs.anl.gov Mon Jan 20 14:52:04 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Mon, 20 Jan 2014 14:52:04 -0600 (CST) Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , Message-ID: Hi Kamal, You'll need to compute your own tke by manipulating the velocity fields. You can get running averages of the requisite quantities via calls to "avg_all" which is found in navier5.f You can compute shear stress on the wall simply by computing the drag on the wall, which can be done via a call to torque_calc(), also found in navier5.f If you cd to /examples and type: grep torq */*.usr you'll find many examples of calls to torque_calc. You simply need to prescribe the surfaces on which shear is to be integrated. I typically write a routine "set_obj" to identify such surfaces on the first call to usrchk. grep set_obj */*.usr will show similar examples. I would recommend trying this for laminar Poiseiulle flow in a very simple channel just to check that your calls are properly set. Best, Paul On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > Hi Paul, > > Thanks and that helped. > > Where can I find the variables like Turbulent KE , shear stress on the wall. ? > > Do i have to activate some parameters for calculating them ? > > If I had to plot them. > > Thanks, > Kamal > > > On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov wrote: > >> >> Kamal, >> >> Looks good. >> >> I'm guessing that one further refinement would be: >> >> if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) >> if (z.gt.z1) scale = smax >> >> which would yield >> >> scale = 1 when z=z0 >> scale = smax when z >= z1 >> >> Paul >> >> >> >> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >> >>> Hi paul, >>> >>> The code works fine, but there should be a small change thats has to be done >>> >>> >>> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >>> if (z.gt.z1) scale = smax >>> >>> This creates a perfect diverging pipe. >>> >>> Thanks for the help paul. >>> >>> Kamal >>> >>> On Jan 20, 2014, at 12:09 AM, nek5000-users at lists.mcs.anl.gov wrote: >>> >>>> Hi paul, >>>> >>>> If I am not wrong, >>>> I make a mesh with three straight pipes( inlet, divergent, outlet ) connected together via n2to3 so that I know the element connectivity places of the divergent section (z0,z1) and use the section what you gave >>>> >>>> Thank you for the code >>>> >>>> Kamal >>>> >>>> On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> >>>>> Kamal, >>>>> >>>>> I would do the following in usrdat2(): >>>>> >>>>> n=nx1*ny1*nz1*nelt >>>>> >>>>> do i=1,n >>>>> x=xm1(i,1,1,1) >>>>> y=ym1(i,1,1,1) >>>>> z=ym1(i,1,1,1) >>>>> scale = 1. >>>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>>> if (z.gt.z1) scale = smax >>>>> xm1(i,1,1,1) = scale*x >>>>> ym1(i,1,1,1) = scale*y >>>>> enddo >>>>> >>>>> Paul >>>>> >>>>> Make certain that z1 and z0 correspond to z values >>>>> that precisely coincide with element interfaces. >>>>> >>>>> >>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>>> Hi Paul, >>>>>> >>>>>> I looked into the Peris example but It is so what same like the stenosis example with a Cosine deformation. >>>>>> >>>>>> In my case it is a pipe with conical divergent. I tried to play around the variables Xm1, Ym1 and Zm1 but the mapping doesn't go well. >>>>>> >>>>>> Could you please help me with this. >>>>>> >>>>>> Thank you, >>>>>> >>>>>> Kamal >>>>>> >>>>>> >>>>>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>>> Hi Paul, >>>>>>> >>>>>>> I looked at the Helix and stenosis example but they are using cosine functions to deform >>>>>>> >>>>>>> I tried to use a tangent function but it bends the whole pipe. >>>>>>> >>>>>>> I dint look at peris example . >>>>>>> >>>>>>> I will take a look at it and let you know. >>>>>>> >>>>>>> Thank you >>>>>>> >>>>>>> Kamal >>>>>>> >>>>>>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>>> >>>>>>>> Kamal, >>>>>>>> >>>>>>>> Have you looked at the peris example? The usr file there shows how to deform >>>>>>>> a pipe geometry. >>>>>>>> >>>>>>>> Paul >>>>>>>> >>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>>> >>>>>>>> Dear Paul, >>>>>>>> >>>>>>>> I tried many ways to map my straight pipe geometry but it does not seem to work properly >>>>>>>> >>>>>>>> I used something like >>>>>>>> >>>>>>>> X = X + Z * tan ( alpha ) >>>>>>>> Y = Y + Z* tan (alpha ) >>>>>>>> >>>>>>>> >>>>>>>> even that dint work. could please help me with this >>>>>>>> >>>>>>>> Thank you >>>>>>>> >>>>>>>> Kamal. >>>>>>>> >>>>>>>> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> >>>>>>>>> Hi Paul, >>>>>>>>> >>>>>>>>> Thanks paul. I tried working with the diverging mesh modification. >>>>>>>>> >>>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>>> >>>>>>>>> z = mx + b >>>>>>>>> z = ny + c >>>>>>>>> >>>>>>>>> x = ( z - b ) / m >>>>>>>>> y = (z - c) / n >>>>>>>>> >>>>>>>>> Do you think would work ? or is there any other way to input that ? >>>>>>>>> >>>>>>>>> Thanks, >>>>>>>>> >>>>>>>>> Kamal >>>>>>>>> >>>>>>>>> >>>>>>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>>> Kamal, >>>>>>>>>> >>>>>>>>>> 1) To check for convergence, run your simulation for increasing polynomial orders ( lx1 in the SIZE file) and measure some consistent quantity (drag, TKE, etc). You can plot this quantity against lx1 and this should give you a good picture of how you are converging (without needing to change the physical mesh). >>>>>>>>>> >>>>>>>>>> 2) If you weren't using temperature in your simulation, you could do put the following code snippet in your userchk >>>>>>>>>> >>>>>>>>>> c------------------------------------------- >>>>>>>>>> integer i, ntot >>>>>>>>>> >>>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in simulation (on THIS processor) >>>>>>>>>> >>>>>>>>>> do i = 1,ntot >>>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + vz(i,1,1,1)**2) >>>>>>>>>> enddo >>>>>>>>>> >>>>>>>>>> ifto = .true. >>>>>>>>>> c------------------------------------------- >>>>>>>>>> >>>>>>>>>> I've assumed here that your density is unity. This computed kinetic energy point-wise and stores it in the temperature field. The part "ifto = .true." tells Nek to output the temperature field whenever it outputs a field file. You could then view this in visit just like you would the velocity field. >>>>>>>>>> >>>>>>>>>> Hope this helps! >>>>>>>>>> >>>>>>>>>> Josh >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, wrote: >>>>>>>>>> Hi Paul, >>>>>>>>>> >>>>>>>>>> I will try that mapping, I created a straight pipe to do some simulations. >>>>>>>>>> >>>>>>>>>> 1) Is there a way to check my spectral convergence, so that I can do some mesh convergence study? >>>>>>>>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>>>>>>>> >>>>>>>>>> Thank you, >>>>>>>>>> Kamal >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>> >>>>>>>>>> Hi Kamal, >>>>>>>>>> >>>>>>>>>> For the geometry you describe, I would apply mesh morphing >>>>>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>>>>> using a subset of the mkmesh script provided in the expansion >>>>>>>>>> example. >>>>>>>>>> >>>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>>> certain that the change in slope occurs at element boundaries, >>>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>>> >>>>>>>>>> _______________ >>>>>>>>>> /| | | >>>>>>>>>> / | | | >>>>>>>>>> /| | | | >>>>>>>>>> ________________/ | | | | >>>>>>>>>> | | | | | | | | >>>>>>>>>> | | | | | | | | >>>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> Paul >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>> >>>>>>>>>> Hi Paul, >>>>>>>>>> >>>>>>>>>> I looked at the example and it looks very helpful, but for a sudden expansion we have only two parts (i.e) the inlet pipe and the outlet pipe. Whereas in a diverging pipe we have three section (i.e,) The inlet pipe, Diverging section and the outlet pipe. >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> Is it possible for me to create a 2D diverging section using mesh modification and revolve it around the centre axis to get a 3d diverging pipe ? >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> or should I apply the mesh modification directly to the 3d sudden expansion pipe using usrdat2() ? >>>>>>>>>> >>>>>>>>>> Thanks, >>>>>>>>>> Kamal >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>> Hi Paul, >>>>>>>>>> >>>>>>>>>> Thanks a lot for the update. I will take a look at as soon as possible and keep you updated with it. >>>>>>>>>> >>>>>>>>>> Thank you, >>>>>>>>>> >>>>>>>>>> Kamal >>>>>>>>>> >>>>>>>>>> On Jan 14, 2014, at 9:04 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>> >>>>>>>>>> Kamal, >>>>>>>>>> >>>>>>>>>> I've added an example for a step-type expansion in a pipe. New example directory >>>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>>> >>>>>>>>>> If you want a standard diffuser, I would use mesh-morphing, as outlined in the >>>>>>>>>> nek primer, which can be found on this page: >>>>>>>>>> >>>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>>> >>>>>>>>>> I've also automated our turbulent outflow bc treatment -- one simply provides an >>>>>>>>>> expansion factor (typically ~ 1.5) and two persistent arrays to turb_outflow(), which >>>>>>>>>> is now in navier5.f. This can be useful when very strong vortices are leaving the >>>>>>>>>> domain, which is possible for certain diffuser flow conditions (and others). >>>>>>>>>> >>>>>>>>>> Paul >>>>>>>>>> ________________________________________ >>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf ofnek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>>> >>>>>>>>>> Hi >>>>>>>>>> >>>>>>>>>> Can some one please help me in this because I am new to nek >>>>>>>>>> >>>>>>>>>> 1) How can I create a .rea for a specific geometry say ' A sudden >>>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>>> >>>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> Thank you >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> kamal >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> -- >>>>>>>>>> Josh Camp >>>>>>>>>> >>>>>>>>>> "All that is necessary for the triumph of evil is that good men do nothing" -- Edmund Burke >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > From nek5000-users at lists.mcs.anl.gov Tue Jan 21 06:46:47 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 21 Jan 2014 13:46:47 +0100 Subject: [Nek5000-users] about fix_geom Message-ID: Hello, guys, Have you any experience with the routine fix_geom, which has not been tested for 2d cases as reported. I am trying to use it for a 2d case with curved boundaries not necessarily describable by expressions. When the gll points on bc are rectified to capture the right shape, a call to fix_geom is supposed to reposition the internal gll points following the so-called Gordon-Hall algorithm? I have tested for a simple mesh with only one square element, whose corners are located at (-1,-1), (-1,1), (1,1) and (1,-1). I find that simply moving the internal gll points of one edge (like (-1,-1) to (1,-1)) followed by calling fix_geom does nothing to the internal gll coordinates. Probably some key ingredients are missing here? thanks in advance, lailai From nek5000-users at lists.mcs.anl.gov Tue Jan 21 08:22:59 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 21 Jan 2014 08:22:59 -0600 (CST) Subject: [Nek5000-users] about fix_geom In-Reply-To: References: Message-ID: Hi Lailai, fix_geom was intended to simply repair small rips in the mesh fabric, i.e., to ensure that there are no gaps between curved edges or corners that are slightly separated because of round-off errors in the .rea file, etc. So, it's not surprising that there would be no change for a single element. The way fix_geom is intended to work is to simply average the values of x,y, and z that are shared between elements, and then to use Gordon-Hall to propagate the resultant changes into the interior of each element. Periodic BCs are excluded from the averaging process via a mask. If an element is unchanged by the averaging process then there is no change propagated into its interior. Hope this helps... Paul On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > Hello, guys, > > Have you any experience with the routine fix_geom, which has not been tested > for 2d cases as reported. I am trying to use it for a 2d case with curved > boundaries not necessarily describable by expressions. When the gll points on > bc are rectified to capture the right shape, a call to fix_geom is supposed > to reposition the internal gll points following the so-called Gordon-Hall > algorithm? > > I have tested for a simple mesh with only one square element, whose corners > are located at (-1,-1), (-1,1), (1,1) and (1,-1). I find that simply moving > the internal gll points of one edge (like (-1,-1) to (1,-1)) followed by > calling fix_geom does nothing to the internal gll coordinates. Probably some > key ingredients are missing here? > > thanks in advance, > lailai > > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > From nek5000-users at lists.mcs.anl.gov Tue Jan 21 09:00:01 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 21 Jan 2014 16:00:01 +0100 Subject: [Nek5000-users] about fix_geom In-Reply-To: References: Message-ID: Hello, Paul, Thanks for your quick answer. So the original usage of this subroutine is to correct the interface between two non-matching neighboring elements. The way I understand is wrong. It functions in two steps, first to average and second to propagate info from the rectified boundary. However, from this post https://lists.mcs.anl.gov/mailman/htdig/nek5000-users/2011-May/001319.html I realize that it seems that fix_geom should do the job I want: after I change the gll coordinates on the boundaries based on the Poisson solver, a call to fix_geom will fix the gll points inside the elements, reflecting the corresponding boundary displacements. Is there misunderstanding here? thanks very much. lailai On 1/21/2014 3:22 PM, nek5000-users at lists.mcs.anl.gov wrote: > > > Hi Lailai, > > fix_geom was intended to simply repair small rips in the > mesh fabric, i.e., to ensure that there are no gaps between > curved edges or corners that are slightly separated because of > round-off errors in the .rea file, etc. So, it's not surprising > that there would be no change for a single element. > > The way fix_geom is intended to work is to simply average the > values of x,y, and z that are shared between elements, and then > to use Gordon-Hall to propagate the resultant changes into the > interior of each element. Periodic BCs are excluded from the > averaging process via a mask. If an element is unchanged by > the averaging process then there is no change propagated into > its interior. > > Hope this helps... > > Paul > > > > On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > >> Hello, guys, >> >> Have you any experience with the routine fix_geom, which has not been >> tested >> for 2d cases as reported. I am trying to use it for a 2d case with >> curved >> boundaries not necessarily describable by expressions. When the gll >> points on >> bc are rectified to capture the right shape, a call to fix_geom is >> supposed >> to reposition the internal gll points following the so-called >> Gordon-Hall >> algorithm? >> >> I have tested for a simple mesh with only one square element, whose >> corners >> are located at (-1,-1), (-1,1), (1,1) and (1,-1). I find that simply >> moving >> the internal gll points of one edge (like (-1,-1) to (1,-1)) followed by >> calling fix_geom does nothing to the internal gll coordinates. >> Probably some >> key ingredients are missing here? >> >> thanks in advance, >> lailai >> >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users From nek5000-users at lists.mcs.anl.gov Tue Jan 21 10:24:06 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 21 Jan 2014 17:24:06 +0100 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , Message-ID: Hi Paul, I checked the set_obj subroutine and implemented one in my .USR file. The code seem to run without any errors but I don't find where these variables are getting stored. I use VisIT to visualize my output, even there was no change in it. do I have to define my own output file and write the variables out ? Thanks, Kamal. On 20/01/2014 21:52, nek5000-users at lists.mcs.anl.gov wrote: > > Hi Kamal, > > You'll need to compute your own tke by manipulating the > velocity fields. > > You can get running averages of the requisite quantities > via calls to "avg_all" which is found in navier5.f > > You can compute shear stress on the wall simply by computing > the drag on the wall, which can be done via a call to torque_calc(), > also found in navier5.f > > If you cd to /examples and type: > > grep torq */*.usr > > you'll find many examples of calls to torque_calc. You simply > need to prescribe the surfaces on which shear is to be integrated. > > I typically write a routine "set_obj" to identify such surfaces > on the first call to usrchk. > > grep set_obj */*.usr > > will show similar examples. > > I would recommend trying this for laminar Poiseiulle flow in > a very simple channel just to check that your calls are properly > set. > > Best, > > Paul > > > On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > >> Hi Paul, >> >> Thanks and that helped. >> >> Where can I find the variables like Turbulent KE , shear stress on >> the wall. ? >> >> Do i have to activate some parameters for calculating them ? >> >> If I had to plot them. >> >> Thanks, >> Kamal >> >> >> On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov wrote: >> >>> >>> Kamal, >>> >>> Looks good. >>> >>> I'm guessing that one further refinement would be: >>> >>> if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) >>> if (z.gt.z1) scale = smax >>> >>> which would yield >>> >>> scale = 1 when z=z0 >>> scale = smax when z >= z1 >>> >>> Paul >>> >>> >>> >>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>> >>>> Hi paul, >>>> >>>> The code works fine, but there should be a small change thats has >>>> to be done >>>> >>>> >>>> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >>>> if (z.gt.z1) scale = smax >>>> >>>> This creates a perfect diverging pipe. >>>> >>>> Thanks for the help paul. >>>> >>>> Kamal >>>> >>>> On Jan 20, 2014, at 12:09 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> Hi paul, >>>>> >>>>> If I am not wrong, >>>>> I make a mesh with three straight pipes( inlet, divergent, outlet >>>>> ) connected together via n2to3 so that I know the element >>>>> connectivity places of the divergent section (z0,z1) and use the >>>>> section what you gave >>>>> >>>>> Thank you for the code >>>>> >>>>> Kamal >>>>> >>>>> On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>>> >>>>>> Kamal, >>>>>> >>>>>> I would do the following in usrdat2(): >>>>>> >>>>>> n=nx1*ny1*nz1*nelt >>>>>> >>>>>> do i=1,n >>>>>> x=xm1(i,1,1,1) >>>>>> y=ym1(i,1,1,1) >>>>>> z=ym1(i,1,1,1) >>>>>> scale = 1. >>>>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>>>> if (z.gt.z1) scale = smax >>>>>> xm1(i,1,1,1) = scale*x >>>>>> ym1(i,1,1,1) = scale*y >>>>>> enddo >>>>>> >>>>>> Paul >>>>>> >>>>>> Make certain that z1 and z0 correspond to z values >>>>>> that precisely coincide with element interfaces. >>>>>> >>>>>> >>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>>> Hi Paul, >>>>>>> >>>>>>> I looked into the Peris example but It is so what same like the >>>>>>> stenosis example with a Cosine deformation. >>>>>>> >>>>>>> In my case it is a pipe with conical divergent. I tried to play >>>>>>> around the variables Xm1, Ym1 and Zm1 but the mapping doesn't go >>>>>>> well. >>>>>>> >>>>>>> Could you please help me with this. >>>>>>> >>>>>>> Thank you, >>>>>>> >>>>>>> Kamal >>>>>>> >>>>>>> >>>>>>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>>> Hi Paul, >>>>>>>> >>>>>>>> I looked at the Helix and stenosis example but they are using >>>>>>>> cosine functions to deform >>>>>>>> >>>>>>>> I tried to use a tangent function but it bends the whole pipe. >>>>>>>> >>>>>>>> I dint look at peris example . >>>>>>>> >>>>>>>> I will take a look at it and let you know. >>>>>>>> >>>>>>>> Thank you >>>>>>>> >>>>>>>> Kamal >>>>>>>> >>>>>>>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>> wrote: >>>>>>>> >>>>>>>>> >>>>>>>>> Kamal, >>>>>>>>> >>>>>>>>> Have you looked at the peris example? The usr file there >>>>>>>>> shows how to deform >>>>>>>>> a pipe geometry. >>>>>>>>> >>>>>>>>> Paul >>>>>>>>> >>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>>>> >>>>>>>>> Dear Paul, >>>>>>>>> >>>>>>>>> I tried many ways to map my straight pipe geometry but it does >>>>>>>>> not seem to work properly >>>>>>>>> >>>>>>>>> I used something like >>>>>>>>> >>>>>>>>> X = X + Z * tan ( alpha ) >>>>>>>>> Y = Y + Z* tan (alpha ) >>>>>>>>> >>>>>>>>> >>>>>>>>> even that dint work. could please help me with this >>>>>>>>> >>>>>>>>> Thank you >>>>>>>>> >>>>>>>>> Kamal. >>>>>>>>> >>>>>>>>> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>> wrote: >>>>>>>>> >>>>>>>>>> Hi Paul, >>>>>>>>>> >>>>>>>>>> Thanks paul. I tried working with the diverging mesh >>>>>>>>>> modification. >>>>>>>>>> >>>>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>>>> >>>>>>>>>> z = mx + b >>>>>>>>>> z = ny + c >>>>>>>>>> >>>>>>>>>> x = ( z - b ) / m >>>>>>>>>> y = (z - c) / n >>>>>>>>>> >>>>>>>>>> Do you think would work ? or is there any other way to input >>>>>>>>>> that ? >>>>>>>>>> >>>>>>>>>> Thanks, >>>>>>>>>> >>>>>>>>>> Kamal >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>>>> Kamal, >>>>>>>>>>> >>>>>>>>>>> 1) To check for convergence, run your simulation for >>>>>>>>>>> increasing polynomial orders ( lx1 in the SIZE file) and >>>>>>>>>>> measure some consistent quantity (drag, TKE, etc). You can >>>>>>>>>>> plot this quantity against lx1 and this should give you a >>>>>>>>>>> good picture of how you are converging (without needing to >>>>>>>>>>> change the physical mesh). >>>>>>>>>>> >>>>>>>>>>> 2) If you weren't using temperature in your simulation, you >>>>>>>>>>> could do put the following code snippet in your userchk >>>>>>>>>>> >>>>>>>>>>> c------------------------------------------- >>>>>>>>>>> integer i, ntot >>>>>>>>>>> >>>>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in >>>>>>>>>>> simulation (on THIS processor) >>>>>>>>>>> >>>>>>>>>>> do i = 1,ntot >>>>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + >>>>>>>>>>> vz(i,1,1,1)**2) >>>>>>>>>>> enddo >>>>>>>>>>> >>>>>>>>>>> ifto = .true. >>>>>>>>>>> c------------------------------------------- >>>>>>>>>>> >>>>>>>>>>> I've assumed here that your density is unity. This computed >>>>>>>>>>> kinetic energy point-wise and stores it in the temperature >>>>>>>>>>> field. The part "ifto = .true." tells Nek to output the >>>>>>>>>>> temperature field whenever it outputs a field file. You >>>>>>>>>>> could then view this in visit just like you would the >>>>>>>>>>> velocity field. >>>>>>>>>>> >>>>>>>>>>> Hope this helps! >>>>>>>>>>> >>>>>>>>>>> Josh >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, >>>>>>>>>>> wrote: >>>>>>>>>>> Hi Paul, >>>>>>>>>>> >>>>>>>>>>> I will try that mapping, I created a straight pipe to do >>>>>>>>>>> some simulations. >>>>>>>>>>> >>>>>>>>>>> 1) Is there a way to check my spectral convergence, so that >>>>>>>>>>> I can do some mesh convergence study? >>>>>>>>>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>>>>>>>>> >>>>>>>>>>> Thank you, >>>>>>>>>>> Kamal >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>> >>>>>>>>>>> Hi Kamal, >>>>>>>>>>> >>>>>>>>>>> For the geometry you describe, I would apply mesh morphing >>>>>>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>>>>>> using a subset of the mkmesh script provided in the expansion >>>>>>>>>>> example. >>>>>>>>>>> >>>>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>>>> certain that the change in slope occurs at element boundaries, >>>>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>>>> >>>>>>>>>>> _______________ >>>>>>>>>>> /| | | >>>>>>>>>>> / | | | >>>>>>>>>>> /| | | | >>>>>>>>>>> ________________/ | | | | >>>>>>>>>>> | | | | | | | | >>>>>>>>>>> | | | | | | | | >>>>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> Paul >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>> >>>>>>>>>>> Hi Paul, >>>>>>>>>>> >>>>>>>>>>> I looked at the example and it looks very helpful, but for a >>>>>>>>>>> sudden expansion we have only two parts (i.e) the inlet pipe >>>>>>>>>>> and the outlet pipe. Whereas in a diverging pipe we have >>>>>>>>>>> three section (i.e,) The inlet pipe, Diverging section and >>>>>>>>>>> the outlet pipe. >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> Is it possible for me to create a 2D diverging section using >>>>>>>>>>> mesh modification and revolve it around the centre axis to >>>>>>>>>>> get a 3d diverging pipe ? >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> or should I apply the mesh modification directly to the 3d >>>>>>>>>>> sudden expansion pipe using usrdat2() ? >>>>>>>>>>> >>>>>>>>>>> Thanks, >>>>>>>>>>> Kamal >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>> Hi Paul, >>>>>>>>>>> >>>>>>>>>>> Thanks a lot for the update. I will take a look at as soon >>>>>>>>>>> as possible and keep you updated with it. >>>>>>>>>>> >>>>>>>>>>> Thank you, >>>>>>>>>>> >>>>>>>>>>> Kamal >>>>>>>>>>> >>>>>>>>>>> On Jan 14, 2014, at 9:04 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> wrote: >>>>>>>>>>> >>>>>>>>>>> Kamal, >>>>>>>>>>> >>>>>>>>>>> I've added an example for a step-type expansion in a pipe. >>>>>>>>>>> New example directory >>>>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>>>> >>>>>>>>>>> If you want a standard diffuser, I would use mesh-morphing, >>>>>>>>>>> as outlined in the >>>>>>>>>>> nek primer, which can be found on this page: >>>>>>>>>>> >>>>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>>>> >>>>>>>>>>> I've also automated our turbulent outflow bc treatment -- >>>>>>>>>>> one simply provides an >>>>>>>>>>> expansion factor (typically ~ 1.5) and two persistent arrays >>>>>>>>>>> to turb_outflow(), which >>>>>>>>>>> is now in navier5.f. This can be useful when very strong >>>>>>>>>>> vortices are leaving the >>>>>>>>>>> domain, which is possible for certain diffuser flow >>>>>>>>>>> conditions (and others). >>>>>>>>>>> >>>>>>>>>>> Paul >>>>>>>>>>> ________________________________________ >>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf >>>>>>>>>>> ofnek5000-users at lists.mcs.anl.gov >>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>>>> >>>>>>>>>>> Hi >>>>>>>>>>> >>>>>>>>>>> Can some one please help me in this because I am new to nek >>>>>>>>>>> >>>>>>>>>>> 1) How can I create a .rea for a specific geometry say ' A >>>>>>>>>>> sudden >>>>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>>>> >>>>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> Thank you >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> kamal >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> -- >>>>>>>>>>> Josh Camp >>>>>>>>>>> >>>>>>>>>>> "All that is necessary for the triumph of evil is that good >>>>>>>>>>> men do nothing" -- Edmund Burke >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users From nek5000-users at lists.mcs.anl.gov Tue Jan 21 10:32:13 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 21 Jan 2014 10:32:13 -0600 (CST) Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , Message-ID: Hi Kamal, Your integrated drag quantities should be written to the logfile (stdout), assuming you've set the arguments in the call to be .true. Paul On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > Hi Paul, > > I checked the set_obj subroutine and implemented one in my .USR file. The > code seem to run without any errors but I don't find where these variables > are getting stored. > > I use VisIT to visualize my output, even there was no change in it. > > do I have to define my own output file and write the variables out ? > > Thanks, > > Kamal. > > > On 20/01/2014 21:52, nek5000-users at lists.mcs.anl.gov wrote: >> >> Hi Kamal, >> >> You'll need to compute your own tke by manipulating the >> velocity fields. >> >> You can get running averages of the requisite quantities >> via calls to "avg_all" which is found in navier5.f >> >> You can compute shear stress on the wall simply by computing >> the drag on the wall, which can be done via a call to torque_calc(), >> also found in navier5.f >> >> If you cd to /examples and type: >> >> grep torq */*.usr >> >> you'll find many examples of calls to torque_calc. You simply >> need to prescribe the surfaces on which shear is to be integrated. >> >> I typically write a routine "set_obj" to identify such surfaces >> on the first call to usrchk. >> >> grep set_obj */*.usr >> >> will show similar examples. >> >> I would recommend trying this for laminar Poiseiulle flow in >> a very simple channel just to check that your calls are properly >> set. >> >> Best, >> >> Paul >> >> >> On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >> >>> Hi Paul, >>> >>> Thanks and that helped. >>> >>> Where can I find the variables like Turbulent KE , shear stress on the >>> wall. ? >>> >>> Do i have to activate some parameters for calculating them ? >>> >>> If I had to plot them. >>> >>> Thanks, >>> Kamal >>> >>> >>> On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov wrote: >>> >>>> >>>> Kamal, >>>> >>>> Looks good. >>>> >>>> I'm guessing that one further refinement would be: >>>> >>>> if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) >>>> if (z.gt.z1) scale = smax >>>> >>>> which would yield >>>> >>>> scale = 1 when z=z0 >>>> scale = smax when z >= z1 >>>> >>>> Paul >>>> >>>> >>>> >>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> Hi paul, >>>>> >>>>> The code works fine, but there should be a small change thats has to be >>>>> done >>>>> >>>>> >>>>> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >>>>> if (z.gt.z1) scale = smax >>>>> >>>>> This creates a perfect diverging pipe. >>>>> >>>>> Thanks for the help paul. >>>>> >>>>> Kamal >>>>> >>>>> On Jan 20, 2014, at 12:09 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>>> Hi paul, >>>>>> >>>>>> If I am not wrong, >>>>>> I make a mesh with three straight pipes( inlet, divergent, outlet ) >>>>>> connected together via n2to3 so that I know the element connectivity >>>>>> places of the divergent section (z0,z1) and use the section what you >>>>>> gave >>>>>> >>>>>> Thank you for the code >>>>>> >>>>>> Kamal >>>>>> >>>>>> On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>>> >>>>>>> Kamal, >>>>>>> >>>>>>> I would do the following in usrdat2(): >>>>>>> >>>>>>> n=nx1*ny1*nz1*nelt >>>>>>> >>>>>>> do i=1,n >>>>>>> x=xm1(i,1,1,1) >>>>>>> y=ym1(i,1,1,1) >>>>>>> z=ym1(i,1,1,1) >>>>>>> scale = 1. >>>>>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>>>>> if (z.gt.z1) scale = smax >>>>>>> xm1(i,1,1,1) = scale*x >>>>>>> ym1(i,1,1,1) = scale*y >>>>>>> enddo >>>>>>> >>>>>>> Paul >>>>>>> >>>>>>> Make certain that z1 and z0 correspond to z values >>>>>>> that precisely coincide with element interfaces. >>>>>>> >>>>>>> >>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>>> Hi Paul, >>>>>>>> >>>>>>>> I looked into the Peris example but It is so what same like the >>>>>>>> stenosis example with a Cosine deformation. >>>>>>>> >>>>>>>> In my case it is a pipe with conical divergent. I tried to play >>>>>>>> around the variables Xm1, Ym1 and Zm1 but the mapping doesn't go >>>>>>>> well. >>>>>>>> >>>>>>>> Could you please help me with this. >>>>>>>> >>>>>>>> Thank you, >>>>>>>> >>>>>>>> Kamal >>>>>>>> >>>>>>>> >>>>>>>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> >>>>>>>>> Hi Paul, >>>>>>>>> >>>>>>>>> I looked at the Helix and stenosis example but they are using cosine >>>>>>>>> functions to deform >>>>>>>>> >>>>>>>>> I tried to use a tangent function but it bends the whole pipe. >>>>>>>>> >>>>>>>>> I dint look at peris example . >>>>>>>>> >>>>>>>>> I will take a look at it and let you know. >>>>>>>>> >>>>>>>>> Thank you >>>>>>>>> >>>>>>>>> Kamal >>>>>>>>> >>>>>>>>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>> >>>>>>>>>> >>>>>>>>>> Kamal, >>>>>>>>>> >>>>>>>>>> Have you looked at the peris example? The usr file there shows how >>>>>>>>>> to deform >>>>>>>>>> a pipe geometry. >>>>>>>>>> >>>>>>>>>> Paul >>>>>>>>>> >>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>>>>> >>>>>>>>>> Dear Paul, >>>>>>>>>> >>>>>>>>>> I tried many ways to map my straight pipe geometry but it does not >>>>>>>>>> seem to work properly >>>>>>>>>> >>>>>>>>>> I used something like >>>>>>>>>> >>>>>>>>>> X = X + Z * tan ( alpha ) >>>>>>>>>> Y = Y + Z* tan (alpha ) >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> even that dint work. could please help me with this >>>>>>>>>> >>>>>>>>>> Thank you >>>>>>>>>> >>>>>>>>>> Kamal. >>>>>>>>>> >>>>>>>>>> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>> >>>>>>>>>>> Hi Paul, >>>>>>>>>>> >>>>>>>>>>> Thanks paul. I tried working with the diverging mesh modification. >>>>>>>>>>> >>>>>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>>>>> >>>>>>>>>>> z = mx + b >>>>>>>>>>> z = ny + c >>>>>>>>>>> >>>>>>>>>>> x = ( z - b ) / m >>>>>>>>>>> y = (z - c) / n >>>>>>>>>>> >>>>>>>>>>> Do you think would work ? or is there any other way to input that >>>>>>>>>>> ? >>>>>>>>>>> >>>>>>>>>>> Thanks, >>>>>>>>>>> >>>>>>>>>>> Kamal >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>>>>> Kamal, >>>>>>>>>>>> >>>>>>>>>>>> 1) To check for convergence, run your simulation for increasing >>>>>>>>>>>> polynomial orders ( lx1 in the SIZE file) and measure some >>>>>>>>>>>> consistent quantity (drag, TKE, etc). You can plot this quantity >>>>>>>>>>>> against lx1 and this should give you a good picture of how you >>>>>>>>>>>> are converging (without needing to change the physical mesh). >>>>>>>>>>>> >>>>>>>>>>>> 2) If you weren't using temperature in your simulation, you could >>>>>>>>>>>> do put the following code snippet in your userchk >>>>>>>>>>>> >>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>> integer i, ntot >>>>>>>>>>>> >>>>>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in simulation >>>>>>>>>>>> (on THIS processor) >>>>>>>>>>>> >>>>>>>>>>>> do i = 1,ntot >>>>>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + >>>>>>>>>>>> vz(i,1,1,1)**2) >>>>>>>>>>>> enddo >>>>>>>>>>>> >>>>>>>>>>>> ifto = .true. >>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>> >>>>>>>>>>>> I've assumed here that your density is unity. This computed >>>>>>>>>>>> kinetic energy point-wise and stores it in the temperature field. >>>>>>>>>>>> The part "ifto = .true." tells Nek to output the temperature >>>>>>>>>>>> field whenever it outputs a field file. You could then view this >>>>>>>>>>>> in visit just like you would the velocity field. >>>>>>>>>>>> >>>>>>>>>>>> Hope this helps! >>>>>>>>>>>> >>>>>>>>>>>> Josh >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, >>>>>>>>>>>> wrote: >>>>>>>>>>>> Hi Paul, >>>>>>>>>>>> >>>>>>>>>>>> I will try that mapping, I created a straight pipe to do some >>>>>>>>>>>> simulations. >>>>>>>>>>>> >>>>>>>>>>>> 1) Is there a way to check my spectral convergence, so that I can >>>>>>>>>>>> do some mesh convergence study? >>>>>>>>>>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>>>>>>>>>> >>>>>>>>>>>> Thank you, >>>>>>>>>>>> Kamal >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>> >>>>>>>>>>>> Hi Kamal, >>>>>>>>>>>> >>>>>>>>>>>> For the geometry you describe, I would apply mesh morphing >>>>>>>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>>>>>>> using a subset of the mkmesh script provided in the expansion >>>>>>>>>>>> example. >>>>>>>>>>>> >>>>>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>>>>> certain that the change in slope occurs at element boundaries, >>>>>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>>>>> >>>>>>>>>>>> _______________ >>>>>>>>>>>> /| | | >>>>>>>>>>>> / | | | >>>>>>>>>>>> /| | | | >>>>>>>>>>>> ________________/ | | | | >>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> Paul >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>> >>>>>>>>>>>> Hi Paul, >>>>>>>>>>>> >>>>>>>>>>>> I looked at the example and it looks very helpful, but for a >>>>>>>>>>>> sudden expansion we have only two parts (i.e) the inlet pipe and >>>>>>>>>>>> the outlet pipe. Whereas in a diverging pipe we have three >>>>>>>>>>>> section (i.e,) The inlet pipe, Diverging section and the outlet >>>>>>>>>>>> pipe. >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> Is it possible for me to create a 2D diverging section using mesh >>>>>>>>>>>> modification and revolve it around the centre axis to get a 3d >>>>>>>>>>>> diverging pipe ? >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> or should I apply the mesh modification directly to the 3d sudden >>>>>>>>>>>> expansion pipe using usrdat2() ? >>>>>>>>>>>> >>>>>>>>>>>> Thanks, >>>>>>>>>>>> Kamal >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>> Hi Paul, >>>>>>>>>>>> >>>>>>>>>>>> Thanks a lot for the update. I will take a look at as soon as >>>>>>>>>>>> possible and keep you updated with it. >>>>>>>>>>>> >>>>>>>>>>>> Thank you, >>>>>>>>>>>> >>>>>>>>>>>> Kamal >>>>>>>>>>>> >>>>>>>>>>>> On Jan 14, 2014, at 9:04 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> wrote: >>>>>>>>>>>> >>>>>>>>>>>> Kamal, >>>>>>>>>>>> >>>>>>>>>>>> I've added an example for a step-type expansion in a pipe. New >>>>>>>>>>>> example directory >>>>>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>>>>> >>>>>>>>>>>> If you want a standard diffuser, I would use mesh-morphing, as >>>>>>>>>>>> outlined in the >>>>>>>>>>>> nek primer, which can be found on this page: >>>>>>>>>>>> >>>>>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>>>>> >>>>>>>>>>>> I've also automated our turbulent outflow bc treatment -- one >>>>>>>>>>>> simply provides an >>>>>>>>>>>> expansion factor (typically ~ 1.5) and two persistent arrays to >>>>>>>>>>>> turb_outflow(), which >>>>>>>>>>>> is now in navier5.f. This can be useful when very strong >>>>>>>>>>>> vortices are leaving the >>>>>>>>>>>> domain, which is possible for certain diffuser flow conditions >>>>>>>>>>>> (and others). >>>>>>>>>>>> >>>>>>>>>>>> Paul >>>>>>>>>>>> ________________________________________ >>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf >>>>>>>>>>>> ofnek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>>>>> >>>>>>>>>>>> Hi >>>>>>>>>>>> >>>>>>>>>>>> Can some one please help me in this because I am new to nek >>>>>>>>>>>> >>>>>>>>>>>> 1) How can I create a .rea for a specific geometry say ' A sudden >>>>>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>>>>> >>>>>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> Thank you >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> kamal >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> -- >>>>>>>>>>>> Josh Camp >>>>>>>>>>>> >>>>>>>>>>>> "All that is necessary for the triumph of evil is that good men >>>>>>>>>>>> do nothing" -- Edmund Burke >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> >>>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > From nek5000-users at lists.mcs.anl.gov Tue Jan 21 10:33:36 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 21 Jan 2014 17:33:36 +0100 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , Message-ID: Hi paul, can I make this to be drag or shear quantities to be return to the a separate file so that it will easy for me to plot. By the way it gives the integral quantity. Think for example I need to find the shear stress on the wall from the inlet to outlet at a particular time = 2 . How can I do that ? Is there way to find the number of elements in x,y and z direction ? On 21/01/2014 17:32, nek5000-users at lists.mcs.anl.gov wrote: > > Hi Kamal, > > Your integrated drag quantities should be written to the logfile > (stdout), > assuming you've set the arguments in the call to be .true. > > Paul > > On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > >> Hi Paul, >> >> I checked the set_obj subroutine and implemented one in my .USR file. >> The code seem to run without any errors but I don't find where these >> variables are getting stored. >> >> I use VisIT to visualize my output, even there was no change in it. >> >> do I have to define my own output file and write the variables out ? >> >> Thanks, >> >> Kamal. >> >> >> On 20/01/2014 21:52, nek5000-users at lists.mcs.anl.gov wrote: >>> >>> Hi Kamal, >>> >>> You'll need to compute your own tke by manipulating the >>> velocity fields. >>> >>> You can get running averages of the requisite quantities >>> via calls to "avg_all" which is found in navier5.f >>> >>> You can compute shear stress on the wall simply by computing >>> the drag on the wall, which can be done via a call to torque_calc(), >>> also found in navier5.f >>> >>> If you cd to /examples and type: >>> >>> grep torq */*.usr >>> >>> you'll find many examples of calls to torque_calc. You simply >>> need to prescribe the surfaces on which shear is to be integrated. >>> >>> I typically write a routine "set_obj" to identify such surfaces >>> on the first call to usrchk. >>> >>> grep set_obj */*.usr >>> >>> will show similar examples. >>> >>> I would recommend trying this for laminar Poiseiulle flow in >>> a very simple channel just to check that your calls are properly >>> set. >>> >>> Best, >>> >>> Paul >>> >>> >>> On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>> >>>> Hi Paul, >>>> >>>> Thanks and that helped. >>>> >>>> Where can I find the variables like Turbulent KE , shear stress on >>>> the wall. ? >>>> >>>> Do i have to activate some parameters for calculating them ? >>>> >>>> If I had to plot them. >>>> >>>> Thanks, >>>> Kamal >>>> >>>> >>>> On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> >>>>> Kamal, >>>>> >>>>> Looks good. >>>>> >>>>> I'm guessing that one further refinement would be: >>>>> >>>>> if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) >>>>> if (z.gt.z1) scale = smax >>>>> >>>>> which would yield >>>>> >>>>> scale = 1 when z=z0 >>>>> scale = smax when z >= z1 >>>>> >>>>> Paul >>>>> >>>>> >>>>> >>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>>> Hi paul, >>>>>> >>>>>> The code works fine, but there should be a small change thats has >>>>>> to be done >>>>>> >>>>>> >>>>>> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >>>>>> if (z.gt.z1) scale = smax >>>>>> >>>>>> This creates a perfect diverging pipe. >>>>>> >>>>>> Thanks for the help paul. >>>>>> >>>>>> Kamal >>>>>> >>>>>> On Jan 20, 2014, at 12:09 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>>> Hi paul, >>>>>>> >>>>>>> If I am not wrong, >>>>>>> I make a mesh with three straight pipes( inlet, divergent, >>>>>>> outlet ) connected together via n2to3 so that I know the element >>>>>>> connectivity places of the divergent section (z0,z1) and use the >>>>>>> section what you gave >>>>>>> >>>>>>> Thank you for the code >>>>>>> >>>>>>> Kamal >>>>>>> >>>>>>> On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>>> >>>>>>>> Kamal, >>>>>>>> >>>>>>>> I would do the following in usrdat2(): >>>>>>>> >>>>>>>> n=nx1*ny1*nz1*nelt >>>>>>>> >>>>>>>> do i=1,n >>>>>>>> x=xm1(i,1,1,1) >>>>>>>> y=ym1(i,1,1,1) >>>>>>>> z=ym1(i,1,1,1) >>>>>>>> scale = 1. >>>>>>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>>>>>> if (z.gt.z1) scale = smax >>>>>>>> xm1(i,1,1,1) = scale*x >>>>>>>> ym1(i,1,1,1) = scale*y >>>>>>>> enddo >>>>>>>> >>>>>>>> Paul >>>>>>>> >>>>>>>> Make certain that z1 and z0 correspond to z values >>>>>>>> that precisely coincide with element interfaces. >>>>>>>> >>>>>>>> >>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> >>>>>>>>> Hi Paul, >>>>>>>>> >>>>>>>>> I looked into the Peris example but It is so what same like >>>>>>>>> the stenosis example with a Cosine deformation. >>>>>>>>> >>>>>>>>> In my case it is a pipe with conical divergent. I tried to >>>>>>>>> play around the variables Xm1, Ym1 and Zm1 but the mapping >>>>>>>>> doesn't go well. >>>>>>>>> >>>>>>>>> Could you please help me with this. >>>>>>>>> >>>>>>>>> Thank you, >>>>>>>>> >>>>>>>>> Kamal >>>>>>>>> >>>>>>>>> >>>>>>>>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>> wrote: >>>>>>>>> >>>>>>>>>> Hi Paul, >>>>>>>>>> >>>>>>>>>> I looked at the Helix and stenosis example but they are using >>>>>>>>>> cosine functions to deform >>>>>>>>>> >>>>>>>>>> I tried to use a tangent function but it bends the whole pipe. >>>>>>>>>> >>>>>>>>>> I dint look at peris example . >>>>>>>>>> >>>>>>>>>> I will take a look at it and let you know. >>>>>>>>>> >>>>>>>>>> Thank you >>>>>>>>>> >>>>>>>>>> Kamal >>>>>>>>>> >>>>>>>>>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>> wrote: >>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> Kamal, >>>>>>>>>>> >>>>>>>>>>> Have you looked at the peris example? The usr file there >>>>>>>>>>> shows how to deform >>>>>>>>>>> a pipe geometry. >>>>>>>>>>> >>>>>>>>>>> Paul >>>>>>>>>>> >>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>>>>>> >>>>>>>>>>> Dear Paul, >>>>>>>>>>> >>>>>>>>>>> I tried many ways to map my straight pipe geometry but it >>>>>>>>>>> does not seem to work properly >>>>>>>>>>> >>>>>>>>>>> I used something like >>>>>>>>>>> >>>>>>>>>>> X = X + Z * tan ( alpha ) >>>>>>>>>>> Y = Y + Z* tan (alpha ) >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> even that dint work. could please help me with this >>>>>>>>>>> >>>>>>>>>>> Thank you >>>>>>>>>>> >>>>>>>>>>> Kamal. >>>>>>>>>>> >>>>>>>>>>> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> wrote: >>>>>>>>>>> >>>>>>>>>>>> Hi Paul, >>>>>>>>>>>> >>>>>>>>>>>> Thanks paul. I tried working with the diverging mesh >>>>>>>>>>>> modification. >>>>>>>>>>>> >>>>>>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>>>>>> >>>>>>>>>>>> z = mx + b >>>>>>>>>>>> z = ny + c >>>>>>>>>>>> >>>>>>>>>>>> x = ( z - b ) / m >>>>>>>>>>>> y = (z - c) / n >>>>>>>>>>>> >>>>>>>>>>>> Do you think would work ? or is there any other way to >>>>>>>>>>>> input that ? >>>>>>>>>>>> >>>>>>>>>>>> Thanks, >>>>>>>>>>>> >>>>>>>>>>>> Kamal >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>>>>>> Kamal, >>>>>>>>>>>>> >>>>>>>>>>>>> 1) To check for convergence, run your simulation for >>>>>>>>>>>>> increasing polynomial orders ( lx1 in the SIZE file) and >>>>>>>>>>>>> measure some consistent quantity (drag, TKE, etc). You >>>>>>>>>>>>> can plot this quantity against lx1 and this should give >>>>>>>>>>>>> you a good picture of how you are converging (without >>>>>>>>>>>>> needing to change the physical mesh). >>>>>>>>>>>>> >>>>>>>>>>>>> 2) If you weren't using temperature in your simulation, >>>>>>>>>>>>> you could do put the following code snippet in your userchk >>>>>>>>>>>>> >>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>> integer i, ntot >>>>>>>>>>>>> >>>>>>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in >>>>>>>>>>>>> simulation (on THIS processor) >>>>>>>>>>>>> >>>>>>>>>>>>> do i = 1,ntot >>>>>>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + >>>>>>>>>>>>> vz(i,1,1,1)**2) >>>>>>>>>>>>> enddo >>>>>>>>>>>>> >>>>>>>>>>>>> ifto = .true. >>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>> >>>>>>>>>>>>> I've assumed here that your density is unity. This >>>>>>>>>>>>> computed kinetic energy point-wise and stores it in the >>>>>>>>>>>>> temperature field. The part "ifto = .true." tells Nek to >>>>>>>>>>>>> output the temperature field whenever it outputs a field >>>>>>>>>>>>> file. You could then view this in visit just like you >>>>>>>>>>>>> would the velocity field. >>>>>>>>>>>>> >>>>>>>>>>>>> Hope this helps! >>>>>>>>>>>>> >>>>>>>>>>>>> Josh >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, >>>>>>>>>>>>> wrote: >>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>> >>>>>>>>>>>>> I will try that mapping, I created a straight pipe to do >>>>>>>>>>>>> some simulations. >>>>>>>>>>>>> >>>>>>>>>>>>> 1) Is there a way to check my spectral convergence, so >>>>>>>>>>>>> that I can do some mesh convergence study? >>>>>>>>>>>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>>>>>>>>>>> >>>>>>>>>>>>> Thank you, >>>>>>>>>>>>> Kamal >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>> >>>>>>>>>>>>> Hi Kamal, >>>>>>>>>>>>> >>>>>>>>>>>>> For the geometry you describe, I would apply mesh morphing >>>>>>>>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>>>>>>>> using a subset of the mkmesh script provided in the expansion >>>>>>>>>>>>> example. >>>>>>>>>>>>> >>>>>>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>>>>>> certain that the change in slope occurs at element >>>>>>>>>>>>> boundaries, >>>>>>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>>>>>> >>>>>>>>>>>>> _______________ >>>>>>>>>>>>> /| | | >>>>>>>>>>>>> / | | | >>>>>>>>>>>>> /| | | | >>>>>>>>>>>>> ________________/ | | | | >>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> Paul >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>> >>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>> >>>>>>>>>>>>> I looked at the example and it looks very helpful, but for >>>>>>>>>>>>> a sudden expansion we have only two parts (i.e) the inlet >>>>>>>>>>>>> pipe and the outlet pipe. Whereas in a diverging pipe we >>>>>>>>>>>>> have three section (i.e,) The inlet pipe, Diverging >>>>>>>>>>>>> section and the outlet pipe. >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> Is it possible for me to create a 2D diverging section >>>>>>>>>>>>> using mesh modification and revolve it around the centre >>>>>>>>>>>>> axis to get a 3d diverging pipe ? >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> or should I apply the mesh modification directly to the 3d >>>>>>>>>>>>> sudden expansion pipe using usrdat2() ? >>>>>>>>>>>>> >>>>>>>>>>>>> Thanks, >>>>>>>>>>>>> Kamal >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>> >>>>>>>>>>>>> Thanks a lot for the update. I will take a look at as soon >>>>>>>>>>>>> as possible and keep you updated with it. >>>>>>>>>>>>> >>>>>>>>>>>>> Thank you, >>>>>>>>>>>>> >>>>>>>>>>>>> Kamal >>>>>>>>>>>>> >>>>>>>>>>>>> On Jan 14, 2014, at 9:04 PM, >>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>> >>>>>>>>>>>>> Kamal, >>>>>>>>>>>>> >>>>>>>>>>>>> I've added an example for a step-type expansion in a pipe. >>>>>>>>>>>>> New example directory >>>>>>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>>>>>> >>>>>>>>>>>>> If you want a standard diffuser, I would use >>>>>>>>>>>>> mesh-morphing, as outlined in the >>>>>>>>>>>>> nek primer, which can be found on this page: >>>>>>>>>>>>> >>>>>>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>>>>>> >>>>>>>>>>>>> I've also automated our turbulent outflow bc treatment -- >>>>>>>>>>>>> one simply provides an >>>>>>>>>>>>> expansion factor (typically ~ 1.5) and two persistent >>>>>>>>>>>>> arrays to turb_outflow(), which >>>>>>>>>>>>> is now in navier5.f. This can be useful when very >>>>>>>>>>>>> strong vortices are leaving the >>>>>>>>>>>>> domain, which is possible for certain diffuser flow >>>>>>>>>>>>> conditions (and others). >>>>>>>>>>>>> >>>>>>>>>>>>> Paul >>>>>>>>>>>>> ________________________________________ >>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf >>>>>>>>>>>>> ofnek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>>>>>> >>>>>>>>>>>>> Hi >>>>>>>>>>>>> >>>>>>>>>>>>> Can some one please help me in this because I am new to nek >>>>>>>>>>>>> >>>>>>>>>>>>> 1) How can I create a .rea for a specific geometry say ' A >>>>>>>>>>>>> sudden >>>>>>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>>>>>> >>>>>>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> Thank you >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> kamal >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> -- >>>>>>>>>>>>> Josh Camp >>>>>>>>>>>>> >>>>>>>>>>>>> "All that is necessary for the triumph of evil is that >>>>>>>>>>>>> good men do nothing" -- Edmund Burke >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> >>>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users From nek5000-users at lists.mcs.anl.gov Tue Jan 21 10:41:07 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 21 Jan 2014 10:41:07 -0600 (CST) Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , Message-ID: Kamal, Usually what I would do in your case is to make a copy of the torque_calc routine, rename it, and modify to your specific needs. It essentially provides a template for what needs to happen. Paul On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > Hi paul, > > can I make this to be drag or shear quantities to be return to the a separate > file so that it will easy for me to plot. > > By the way it gives the integral quantity. Think for example I need to find > the shear stress on the wall from the inlet to outlet at a particular time = > 2 . How can I do that ? > > Is there way to find the number of elements in x,y and z direction ? > > On 21/01/2014 17:32, nek5000-users at lists.mcs.anl.gov wrote: >> >> Hi Kamal, >> >> Your integrated drag quantities should be written to the logfile (stdout), >> assuming you've set the arguments in the call to be .true. >> >> Paul >> >> On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >> >>> Hi Paul, >>> >>> I checked the set_obj subroutine and implemented one in my .USR file. The >>> code seem to run without any errors but I don't find where these variables >>> are getting stored. >>> >>> I use VisIT to visualize my output, even there was no change in it. >>> >>> do I have to define my own output file and write the variables out ? >>> >>> Thanks, >>> >>> Kamal. >>> >>> >>> On 20/01/2014 21:52, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>> Hi Kamal, >>>> >>>> You'll need to compute your own tke by manipulating the >>>> velocity fields. >>>> >>>> You can get running averages of the requisite quantities >>>> via calls to "avg_all" which is found in navier5.f >>>> >>>> You can compute shear stress on the wall simply by computing >>>> the drag on the wall, which can be done via a call to torque_calc(), >>>> also found in navier5.f >>>> >>>> If you cd to /examples and type: >>>> >>>> grep torq */*.usr >>>> >>>> you'll find many examples of calls to torque_calc. You simply >>>> need to prescribe the surfaces on which shear is to be integrated. >>>> >>>> I typically write a routine "set_obj" to identify such surfaces >>>> on the first call to usrchk. >>>> >>>> grep set_obj */*.usr >>>> >>>> will show similar examples. >>>> >>>> I would recommend trying this for laminar Poiseiulle flow in >>>> a very simple channel just to check that your calls are properly >>>> set. >>>> >>>> Best, >>>> >>>> Paul >>>> >>>> >>>> On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> Hi Paul, >>>>> >>>>> Thanks and that helped. >>>>> >>>>> Where can I find the variables like Turbulent KE , shear stress on the >>>>> wall. ? >>>>> >>>>> Do i have to activate some parameters for calculating them ? >>>>> >>>>> If I had to plot them. >>>>> >>>>> Thanks, >>>>> Kamal >>>>> >>>>> >>>>> On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>>> >>>>>> Kamal, >>>>>> >>>>>> Looks good. >>>>>> >>>>>> I'm guessing that one further refinement would be: >>>>>> >>>>>> if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) >>>>>> if (z.gt.z1) scale = smax >>>>>> >>>>>> which would yield >>>>>> >>>>>> scale = 1 when z=z0 >>>>>> scale = smax when z >= z1 >>>>>> >>>>>> Paul >>>>>> >>>>>> >>>>>> >>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>>> Hi paul, >>>>>>> >>>>>>> The code works fine, but there should be a small change thats has to >>>>>>> be done >>>>>>> >>>>>>> >>>>>>> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >>>>>>> if (z.gt.z1) scale = smax >>>>>>> >>>>>>> This creates a perfect diverging pipe. >>>>>>> >>>>>>> Thanks for the help paul. >>>>>>> >>>>>>> Kamal >>>>>>> >>>>>>> On Jan 20, 2014, at 12:09 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>>> Hi paul, >>>>>>>> >>>>>>>> If I am not wrong, >>>>>>>> I make a mesh with three straight pipes( inlet, divergent, outlet ) >>>>>>>> connected together via n2to3 so that I know the element connectivity >>>>>>>> places of the divergent section (z0,z1) and use the section what you >>>>>>>> gave >>>>>>>> >>>>>>>> Thank you for the code >>>>>>>> >>>>>>>> Kamal >>>>>>>> >>>>>>>> On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> >>>>>>>>> >>>>>>>>> Kamal, >>>>>>>>> >>>>>>>>> I would do the following in usrdat2(): >>>>>>>>> >>>>>>>>> n=nx1*ny1*nz1*nelt >>>>>>>>> >>>>>>>>> do i=1,n >>>>>>>>> x=xm1(i,1,1,1) >>>>>>>>> y=ym1(i,1,1,1) >>>>>>>>> z=ym1(i,1,1,1) >>>>>>>>> scale = 1. >>>>>>>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>> xm1(i,1,1,1) = scale*x >>>>>>>>> ym1(i,1,1,1) = scale*y >>>>>>>>> enddo >>>>>>>>> >>>>>>>>> Paul >>>>>>>>> >>>>>>>>> Make certain that z1 and z0 correspond to z values >>>>>>>>> that precisely coincide with element interfaces. >>>>>>>>> >>>>>>>>> >>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>> >>>>>>>>>> Hi Paul, >>>>>>>>>> >>>>>>>>>> I looked into the Peris example but It is so what same like the >>>>>>>>>> stenosis example with a Cosine deformation. >>>>>>>>>> >>>>>>>>>> In my case it is a pipe with conical divergent. I tried to play >>>>>>>>>> around the variables Xm1, Ym1 and Zm1 but the mapping doesn't go >>>>>>>>>> well. >>>>>>>>>> >>>>>>>>>> Could you please help me with this. >>>>>>>>>> >>>>>>>>>> Thank you, >>>>>>>>>> >>>>>>>>>> Kamal >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>> >>>>>>>>>>> Hi Paul, >>>>>>>>>>> >>>>>>>>>>> I looked at the Helix and stenosis example but they are using >>>>>>>>>>> cosine functions to deform >>>>>>>>>>> >>>>>>>>>>> I tried to use a tangent function but it bends the whole pipe. >>>>>>>>>>> >>>>>>>>>>> I dint look at peris example . >>>>>>>>>>> >>>>>>>>>>> I will take a look at it and let you know. >>>>>>>>>>> >>>>>>>>>>> Thank you >>>>>>>>>>> >>>>>>>>>>> Kamal >>>>>>>>>>> >>>>>>>>>>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> wrote: >>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> Kamal, >>>>>>>>>>>> >>>>>>>>>>>> Have you looked at the peris example? The usr file there shows >>>>>>>>>>>> how to deform >>>>>>>>>>>> a pipe geometry. >>>>>>>>>>>> >>>>>>>>>>>> Paul >>>>>>>>>>>> >>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>>>>>>> >>>>>>>>>>>> Dear Paul, >>>>>>>>>>>> >>>>>>>>>>>> I tried many ways to map my straight pipe geometry but it does >>>>>>>>>>>> not seem to work properly >>>>>>>>>>>> >>>>>>>>>>>> I used something like >>>>>>>>>>>> >>>>>>>>>>>> X = X + Z * tan ( alpha ) >>>>>>>>>>>> Y = Y + Z* tan (alpha ) >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> even that dint work. could please help me with this >>>>>>>>>>>> >>>>>>>>>>>> Thank you >>>>>>>>>>>> >>>>>>>>>>>> Kamal. >>>>>>>>>>>> >>>>>>>>>>>> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> wrote: >>>>>>>>>>>> >>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>> >>>>>>>>>>>>> Thanks paul. I tried working with the diverging mesh >>>>>>>>>>>>> modification. >>>>>>>>>>>>> >>>>>>>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>>>>>>> >>>>>>>>>>>>> z = mx + b >>>>>>>>>>>>> z = ny + c >>>>>>>>>>>>> >>>>>>>>>>>>> x = ( z - b ) / m >>>>>>>>>>>>> y = (z - c) / n >>>>>>>>>>>>> >>>>>>>>>>>>> Do you think would work ? or is there any other way to input >>>>>>>>>>>>> that ? >>>>>>>>>>>>> >>>>>>>>>>>>> Thanks, >>>>>>>>>>>>> >>>>>>>>>>>>> Kamal >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>> >>>>>>>>>>>>>> 1) To check for convergence, run your simulation for increasing >>>>>>>>>>>>>> polynomial orders ( lx1 in the SIZE file) and measure some >>>>>>>>>>>>>> consistent quantity (drag, TKE, etc). You can plot this >>>>>>>>>>>>>> quantity against lx1 and this should give you a good picture of >>>>>>>>>>>>>> how you are converging (without needing to change the physical >>>>>>>>>>>>>> mesh). >>>>>>>>>>>>>> >>>>>>>>>>>>>> 2) If you weren't using temperature in your simulation, you >>>>>>>>>>>>>> could do put the following code snippet in your userchk >>>>>>>>>>>>>> >>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>> integer i, ntot >>>>>>>>>>>>>> >>>>>>>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in simulation >>>>>>>>>>>>>> (on THIS processor) >>>>>>>>>>>>>> >>>>>>>>>>>>>> do i = 1,ntot >>>>>>>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + >>>>>>>>>>>>>> vz(i,1,1,1)**2) >>>>>>>>>>>>>> enddo >>>>>>>>>>>>>> >>>>>>>>>>>>>> ifto = .true. >>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>> >>>>>>>>>>>>>> I've assumed here that your density is unity. This computed >>>>>>>>>>>>>> kinetic energy point-wise and stores it in the temperature >>>>>>>>>>>>>> field. The part "ifto = .true." tells Nek to output the >>>>>>>>>>>>>> temperature field whenever it outputs a field file. You could >>>>>>>>>>>>>> then view this in visit just like you would the velocity field. >>>>>>>>>>>>>> >>>>>>>>>>>>>> Hope this helps! >>>>>>>>>>>>>> >>>>>>>>>>>>>> Josh >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, >>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> I will try that mapping, I created a straight pipe to do some >>>>>>>>>>>>>> simulations. >>>>>>>>>>>>>> >>>>>>>>>>>>>> 1) Is there a way to check my spectral convergence, so that I >>>>>>>>>>>>>> can do some mesh convergence study? >>>>>>>>>>>>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>> Hi Kamal, >>>>>>>>>>>>>> >>>>>>>>>>>>>> For the geometry you describe, I would apply mesh morphing >>>>>>>>>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>>>>>>>>> using a subset of the mkmesh script provided in the expansion >>>>>>>>>>>>>> example. >>>>>>>>>>>>>> >>>>>>>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>>>>>>> certain that the change in slope occurs at element boundaries, >>>>>>>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________ >>>>>>>>>>>>>> /| | | >>>>>>>>>>>>>> / | | | >>>>>>>>>>>>>> /| | | | >>>>>>>>>>>>>> ________________/ | | | | >>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> Paul >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> I looked at the example and it looks very helpful, but for a >>>>>>>>>>>>>> sudden expansion we have only two parts (i.e) the inlet pipe >>>>>>>>>>>>>> and the outlet pipe. Whereas in a diverging pipe we have three >>>>>>>>>>>>>> section (i.e,) The inlet pipe, Diverging section and the outlet >>>>>>>>>>>>>> pipe. >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> Is it possible for me to create a 2D diverging section using >>>>>>>>>>>>>> mesh modification and revolve it around the centre axis to get >>>>>>>>>>>>>> a 3d diverging pipe ? >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> or should I apply the mesh modification directly to the 3d >>>>>>>>>>>>>> sudden expansion pipe using usrdat2() ? >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thanks a lot for the update. I will take a look at as soon as >>>>>>>>>>>>>> possible and keep you updated with it. >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Jan 14, 2014, at 9:04 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>> >>>>>>>>>>>>>> I've added an example for a step-type expansion in a pipe. New >>>>>>>>>>>>>> example directory >>>>>>>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>>>>>>> >>>>>>>>>>>>>> If you want a standard diffuser, I would use mesh-morphing, as >>>>>>>>>>>>>> outlined in the >>>>>>>>>>>>>> nek primer, which can be found on this page: >>>>>>>>>>>>>> >>>>>>>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>>>>>>> >>>>>>>>>>>>>> I've also automated our turbulent outflow bc treatment -- one >>>>>>>>>>>>>> simply provides an >>>>>>>>>>>>>> expansion factor (typically ~ 1.5) and two persistent arrays to >>>>>>>>>>>>>> turb_outflow(), which >>>>>>>>>>>>>> is now in navier5.f. This can be useful when very strong >>>>>>>>>>>>>> vortices are leaving the >>>>>>>>>>>>>> domain, which is possible for certain diffuser flow conditions >>>>>>>>>>>>>> (and others). >>>>>>>>>>>>>> >>>>>>>>>>>>>> Paul >>>>>>>>>>>>>> ________________________________________ >>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf >>>>>>>>>>>>>> ofnek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>>>>>>> >>>>>>>>>>>>>> Hi >>>>>>>>>>>>>> >>>>>>>>>>>>>> Can some one please help me in this because I am new to nek >>>>>>>>>>>>>> >>>>>>>>>>>>>> 1) How can I create a .rea for a specific geometry say ' A >>>>>>>>>>>>>> sudden >>>>>>>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>>>>>>> >>>>>>>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> kamal >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> -- >>>>>>>>>>>>>> Josh Camp >>>>>>>>>>>>>> >>>>>>>>>>>>>> "All that is necessary for the triumph of evil is that good men >>>>>>>>>>>>>> do nothing" -- Edmund Burke >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> >>>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > From nek5000-users at lists.mcs.anl.gov Tue Jan 21 10:42:28 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 21 Jan 2014 10:42:28 -0600 (CST) Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , Message-ID: PS - I actually don't know of a good way to find the number of elements in each direction... so I normally hard code that into the .usr file and then do a check to make certain that at least the product nelx x nely x nelz = nelgv On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > Hi paul, > > can I make this to be drag or shear quantities to be return to the a separate > file so that it will easy for me to plot. > > By the way it gives the integral quantity. Think for example I need to find > the shear stress on the wall from the inlet to outlet at a particular time = > 2 . How can I do that ? > > Is there way to find the number of elements in x,y and z direction ? > > On 21/01/2014 17:32, nek5000-users at lists.mcs.anl.gov wrote: >> >> Hi Kamal, >> >> Your integrated drag quantities should be written to the logfile (stdout), >> assuming you've set the arguments in the call to be .true. >> >> Paul >> >> On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >> >>> Hi Paul, >>> >>> I checked the set_obj subroutine and implemented one in my .USR file. The >>> code seem to run without any errors but I don't find where these variables >>> are getting stored. >>> >>> I use VisIT to visualize my output, even there was no change in it. >>> >>> do I have to define my own output file and write the variables out ? >>> >>> Thanks, >>> >>> Kamal. >>> >>> >>> On 20/01/2014 21:52, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>> Hi Kamal, >>>> >>>> You'll need to compute your own tke by manipulating the >>>> velocity fields. >>>> >>>> You can get running averages of the requisite quantities >>>> via calls to "avg_all" which is found in navier5.f >>>> >>>> You can compute shear stress on the wall simply by computing >>>> the drag on the wall, which can be done via a call to torque_calc(), >>>> also found in navier5.f >>>> >>>> If you cd to /examples and type: >>>> >>>> grep torq */*.usr >>>> >>>> you'll find many examples of calls to torque_calc. You simply >>>> need to prescribe the surfaces on which shear is to be integrated. >>>> >>>> I typically write a routine "set_obj" to identify such surfaces >>>> on the first call to usrchk. >>>> >>>> grep set_obj */*.usr >>>> >>>> will show similar examples. >>>> >>>> I would recommend trying this for laminar Poiseiulle flow in >>>> a very simple channel just to check that your calls are properly >>>> set. >>>> >>>> Best, >>>> >>>> Paul >>>> >>>> >>>> On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> Hi Paul, >>>>> >>>>> Thanks and that helped. >>>>> >>>>> Where can I find the variables like Turbulent KE , shear stress on the >>>>> wall. ? >>>>> >>>>> Do i have to activate some parameters for calculating them ? >>>>> >>>>> If I had to plot them. >>>>> >>>>> Thanks, >>>>> Kamal >>>>> >>>>> >>>>> On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>>> >>>>>> Kamal, >>>>>> >>>>>> Looks good. >>>>>> >>>>>> I'm guessing that one further refinement would be: >>>>>> >>>>>> if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) >>>>>> if (z.gt.z1) scale = smax >>>>>> >>>>>> which would yield >>>>>> >>>>>> scale = 1 when z=z0 >>>>>> scale = smax when z >= z1 >>>>>> >>>>>> Paul >>>>>> >>>>>> >>>>>> >>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>>> Hi paul, >>>>>>> >>>>>>> The code works fine, but there should be a small change thats has to >>>>>>> be done >>>>>>> >>>>>>> >>>>>>> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >>>>>>> if (z.gt.z1) scale = smax >>>>>>> >>>>>>> This creates a perfect diverging pipe. >>>>>>> >>>>>>> Thanks for the help paul. >>>>>>> >>>>>>> Kamal >>>>>>> >>>>>>> On Jan 20, 2014, at 12:09 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>>> Hi paul, >>>>>>>> >>>>>>>> If I am not wrong, >>>>>>>> I make a mesh with three straight pipes( inlet, divergent, outlet ) >>>>>>>> connected together via n2to3 so that I know the element connectivity >>>>>>>> places of the divergent section (z0,z1) and use the section what you >>>>>>>> gave >>>>>>>> >>>>>>>> Thank you for the code >>>>>>>> >>>>>>>> Kamal >>>>>>>> >>>>>>>> On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> >>>>>>>>> >>>>>>>>> Kamal, >>>>>>>>> >>>>>>>>> I would do the following in usrdat2(): >>>>>>>>> >>>>>>>>> n=nx1*ny1*nz1*nelt >>>>>>>>> >>>>>>>>> do i=1,n >>>>>>>>> x=xm1(i,1,1,1) >>>>>>>>> y=ym1(i,1,1,1) >>>>>>>>> z=ym1(i,1,1,1) >>>>>>>>> scale = 1. >>>>>>>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>> xm1(i,1,1,1) = scale*x >>>>>>>>> ym1(i,1,1,1) = scale*y >>>>>>>>> enddo >>>>>>>>> >>>>>>>>> Paul >>>>>>>>> >>>>>>>>> Make certain that z1 and z0 correspond to z values >>>>>>>>> that precisely coincide with element interfaces. >>>>>>>>> >>>>>>>>> >>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>> >>>>>>>>>> Hi Paul, >>>>>>>>>> >>>>>>>>>> I looked into the Peris example but It is so what same like the >>>>>>>>>> stenosis example with a Cosine deformation. >>>>>>>>>> >>>>>>>>>> In my case it is a pipe with conical divergent. I tried to play >>>>>>>>>> around the variables Xm1, Ym1 and Zm1 but the mapping doesn't go >>>>>>>>>> well. >>>>>>>>>> >>>>>>>>>> Could you please help me with this. >>>>>>>>>> >>>>>>>>>> Thank you, >>>>>>>>>> >>>>>>>>>> Kamal >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>> >>>>>>>>>>> Hi Paul, >>>>>>>>>>> >>>>>>>>>>> I looked at the Helix and stenosis example but they are using >>>>>>>>>>> cosine functions to deform >>>>>>>>>>> >>>>>>>>>>> I tried to use a tangent function but it bends the whole pipe. >>>>>>>>>>> >>>>>>>>>>> I dint look at peris example . >>>>>>>>>>> >>>>>>>>>>> I will take a look at it and let you know. >>>>>>>>>>> >>>>>>>>>>> Thank you >>>>>>>>>>> >>>>>>>>>>> Kamal >>>>>>>>>>> >>>>>>>>>>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> wrote: >>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> Kamal, >>>>>>>>>>>> >>>>>>>>>>>> Have you looked at the peris example? The usr file there shows >>>>>>>>>>>> how to deform >>>>>>>>>>>> a pipe geometry. >>>>>>>>>>>> >>>>>>>>>>>> Paul >>>>>>>>>>>> >>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>>>>>>> >>>>>>>>>>>> Dear Paul, >>>>>>>>>>>> >>>>>>>>>>>> I tried many ways to map my straight pipe geometry but it does >>>>>>>>>>>> not seem to work properly >>>>>>>>>>>> >>>>>>>>>>>> I used something like >>>>>>>>>>>> >>>>>>>>>>>> X = X + Z * tan ( alpha ) >>>>>>>>>>>> Y = Y + Z* tan (alpha ) >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> even that dint work. could please help me with this >>>>>>>>>>>> >>>>>>>>>>>> Thank you >>>>>>>>>>>> >>>>>>>>>>>> Kamal. >>>>>>>>>>>> >>>>>>>>>>>> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> wrote: >>>>>>>>>>>> >>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>> >>>>>>>>>>>>> Thanks paul. I tried working with the diverging mesh >>>>>>>>>>>>> modification. >>>>>>>>>>>>> >>>>>>>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>>>>>>> >>>>>>>>>>>>> z = mx + b >>>>>>>>>>>>> z = ny + c >>>>>>>>>>>>> >>>>>>>>>>>>> x = ( z - b ) / m >>>>>>>>>>>>> y = (z - c) / n >>>>>>>>>>>>> >>>>>>>>>>>>> Do you think would work ? or is there any other way to input >>>>>>>>>>>>> that ? >>>>>>>>>>>>> >>>>>>>>>>>>> Thanks, >>>>>>>>>>>>> >>>>>>>>>>>>> Kamal >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>> >>>>>>>>>>>>>> 1) To check for convergence, run your simulation for increasing >>>>>>>>>>>>>> polynomial orders ( lx1 in the SIZE file) and measure some >>>>>>>>>>>>>> consistent quantity (drag, TKE, etc). You can plot this >>>>>>>>>>>>>> quantity against lx1 and this should give you a good picture of >>>>>>>>>>>>>> how you are converging (without needing to change the physical >>>>>>>>>>>>>> mesh). >>>>>>>>>>>>>> >>>>>>>>>>>>>> 2) If you weren't using temperature in your simulation, you >>>>>>>>>>>>>> could do put the following code snippet in your userchk >>>>>>>>>>>>>> >>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>> integer i, ntot >>>>>>>>>>>>>> >>>>>>>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in simulation >>>>>>>>>>>>>> (on THIS processor) >>>>>>>>>>>>>> >>>>>>>>>>>>>> do i = 1,ntot >>>>>>>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + >>>>>>>>>>>>>> vz(i,1,1,1)**2) >>>>>>>>>>>>>> enddo >>>>>>>>>>>>>> >>>>>>>>>>>>>> ifto = .true. >>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>> >>>>>>>>>>>>>> I've assumed here that your density is unity. This computed >>>>>>>>>>>>>> kinetic energy point-wise and stores it in the temperature >>>>>>>>>>>>>> field. The part "ifto = .true." tells Nek to output the >>>>>>>>>>>>>> temperature field whenever it outputs a field file. You could >>>>>>>>>>>>>> then view this in visit just like you would the velocity field. >>>>>>>>>>>>>> >>>>>>>>>>>>>> Hope this helps! >>>>>>>>>>>>>> >>>>>>>>>>>>>> Josh >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, >>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> I will try that mapping, I created a straight pipe to do some >>>>>>>>>>>>>> simulations. >>>>>>>>>>>>>> >>>>>>>>>>>>>> 1) Is there a way to check my spectral convergence, so that I >>>>>>>>>>>>>> can do some mesh convergence study? >>>>>>>>>>>>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>> Hi Kamal, >>>>>>>>>>>>>> >>>>>>>>>>>>>> For the geometry you describe, I would apply mesh morphing >>>>>>>>>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>>>>>>>>> using a subset of the mkmesh script provided in the expansion >>>>>>>>>>>>>> example. >>>>>>>>>>>>>> >>>>>>>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>>>>>>> certain that the change in slope occurs at element boundaries, >>>>>>>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________ >>>>>>>>>>>>>> /| | | >>>>>>>>>>>>>> / | | | >>>>>>>>>>>>>> /| | | | >>>>>>>>>>>>>> ________________/ | | | | >>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> Paul >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> I looked at the example and it looks very helpful, but for a >>>>>>>>>>>>>> sudden expansion we have only two parts (i.e) the inlet pipe >>>>>>>>>>>>>> and the outlet pipe. Whereas in a diverging pipe we have three >>>>>>>>>>>>>> section (i.e,) The inlet pipe, Diverging section and the outlet >>>>>>>>>>>>>> pipe. >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> Is it possible for me to create a 2D diverging section using >>>>>>>>>>>>>> mesh modification and revolve it around the centre axis to get >>>>>>>>>>>>>> a 3d diverging pipe ? >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> or should I apply the mesh modification directly to the 3d >>>>>>>>>>>>>> sudden expansion pipe using usrdat2() ? >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thanks a lot for the update. I will take a look at as soon as >>>>>>>>>>>>>> possible and keep you updated with it. >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Jan 14, 2014, at 9:04 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>> >>>>>>>>>>>>>> I've added an example for a step-type expansion in a pipe. New >>>>>>>>>>>>>> example directory >>>>>>>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>>>>>>> >>>>>>>>>>>>>> If you want a standard diffuser, I would use mesh-morphing, as >>>>>>>>>>>>>> outlined in the >>>>>>>>>>>>>> nek primer, which can be found on this page: >>>>>>>>>>>>>> >>>>>>>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>>>>>>> >>>>>>>>>>>>>> I've also automated our turbulent outflow bc treatment -- one >>>>>>>>>>>>>> simply provides an >>>>>>>>>>>>>> expansion factor (typically ~ 1.5) and two persistent arrays to >>>>>>>>>>>>>> turb_outflow(), which >>>>>>>>>>>>>> is now in navier5.f. This can be useful when very strong >>>>>>>>>>>>>> vortices are leaving the >>>>>>>>>>>>>> domain, which is possible for certain diffuser flow conditions >>>>>>>>>>>>>> (and others). >>>>>>>>>>>>>> >>>>>>>>>>>>>> Paul >>>>>>>>>>>>>> ________________________________________ >>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf >>>>>>>>>>>>>> ofnek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>>>>>>> >>>>>>>>>>>>>> Hi >>>>>>>>>>>>>> >>>>>>>>>>>>>> Can some one please help me in this because I am new to nek >>>>>>>>>>>>>> >>>>>>>>>>>>>> 1) How can I create a .rea for a specific geometry say ' A >>>>>>>>>>>>>> sudden >>>>>>>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>>>>>>> >>>>>>>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> kamal >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> -- >>>>>>>>>>>>>> Josh Camp >>>>>>>>>>>>>> >>>>>>>>>>>>>> "All that is necessary for the triumph of evil is that good men >>>>>>>>>>>>>> do nothing" -- Edmund Burke >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> >>>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > From nek5000-users at lists.mcs.anl.gov Tue Jan 21 12:35:42 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 21 Jan 2014 19:35:42 +0100 Subject: [Nek5000-users] Projection of linearized equations onto reduced basis In-Reply-To: References: Message-ID: Hi Neks, I would like to project the linearized NS equations onto a reduced basis formed by some POD modes (velocity vectors). We know that the perturbation equations can be read as du(t)/dx = A u(t), where // A = ( -U.grad(u) - u.grad(U) - grad(p) + 1/Re Lap(u)// To obtain the projected system, I need to compute the matrix Ar_i,j = where U_j is the j mode (a vector containing the velocity field). The step that I can't clearly see is the matrix-vector product A U_j. Do I have to explicitily compute the matrix A and then obtain the product? or is there a direct way to do it without this matrix (using the time-stepper)? Thanks in advance! Sincerely, Juan-- From nek5000-users at lists.mcs.anl.gov Tue Jan 21 14:03:34 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 21 Jan 2014 21:03:34 +0100 Subject: [Nek5000-users] Projection of linearized equations onto reduced basis In-Reply-To: References: Message-ID: Hey Juan! It turns out I had been working on a similar problem for the past few days and came up with a small subroutine. It probably is not the most efficient way to do it, but it at least work when I use global direct and adjoint modes . I'll send it to you tomorrow, and if you wanna discuss, I can drop by ONERA next week. Cheers. JC 2014/1/21 > Hi Neks, > > I would like to project the linearized NS equations onto a reduced basis > formed by some POD modes (velocity vectors). > We know that the perturbation equations can be read as du(t)/dx = A u(t), > where > > // A = ( -U.grad(u) - u.grad(U) - grad(p) + 1/Re Lap(u)// > > To obtain the projected system, I need to compute the matrix Ar_i,j = > where U_j is the j mode (a vector containing the velocity > field). > The step that I can't clearly see is the matrix-vector product A U_j. > Do I have to explicitily compute the matrix A and then obtain the > product? or is there a direct way to do it without this matrix (using > the time-stepper)? > > Thanks in advance! > Sincerely, > Juan-- > > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > -- Jean-Christophe Loiseau Homepage -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Tue Jan 21 14:24:49 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 21 Jan 2014 20:24:49 +0000 Subject: [Nek5000-users] horizontal geospatial footprint Message-ID: Dear NEK5000 users desk at the Argonne National Lab, I would like to read in just the lat and lon from a 1.6TB NEK5000 .dat file so that I can plot a bird's eye view geospatial footprint. Please help me with the Nek code. The data and metadata can be downloaded from GRIIDC at the Harte Research Institute, where I work. I appreciate your help! The metadata for the file says, "The binary (*.dat) files that comprise this dataset must be read and processed using NEK5000 software." https://data.gulfresearchinitiative.org/data/R1.x134.115:0002 Susan Susan Renee Rogers, susan.rogers at tamucc.edu Marine and Environmental Data Analyst Harte Research Institute for Gulf of Mexico Studies Texas A&M University at Corpus Christi 6300 Ocean Drive, Unit 5869 Corpus Christi, TX 78412-5869 -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Tue Jan 21 15:58:09 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 21 Jan 2014 15:58:09 -0600 Subject: [Nek5000-users] horizontal geospatial footprint In-Reply-To: References: Message-ID: Hi Susan, If possible, I might suggest getting in touch with the corresponding author first. The reason for this is the .dat extension is not a native format for NEK5000, which means they must have changed it from the original file extension. It would be good to know more details from the author about the contents of the data file; then the developers might be able to better assist you. Josh On Tue, Jan 21, 2014 at 2:24 PM, wrote: > Dear NEK5000 users desk at the Argonne National Lab, > > > > I would like to read in just the lat and lon from a 1.6TB NEK5000 .dat > file so that I can plot a bird?s eye view geospatial footprint. Please > help me with the Nek code. > > > > The data and metadata can be downloaded from GRIIDC at the Harte Research > Institute, where I work. I appreciate your help! > > The metadata for the file says, ?The binary (*.dat) files that comprise > this dataset must be read and processed using NEK5000 software.? > > > > https://data.gulfresearchinitiative.org/data/R1.x134.115:0002 > > > > Susan > > > > *Susan Renee Rogers, susan.rogers at tamucc.edu * > > *Marine and Environmental Data Analyst* > > *Harte Research Institute for Gulf of Mexico Studies* > > *Texas A&M University at Corpus Christi* > > *6300 Ocean Drive, Unit 5869* > > *Corpus Christi, TX 78412-5869* > > > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > -- Josh Camp "All that is necessary for the triumph of evil is that good men do nothing" -- Edmund Burke -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Wed Jan 22 09:07:39 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Wed, 22 Jan 2014 15:07:39 +0000 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , , Message-ID: Hi Kamal, As I thought about it some more, if you're interested in the local wall shear stress magnitude I'm quite certain you can get this by plotting the magnitude of vorticity on the surface in question. (Note that the sign of the WSS, which in fact is a tensor or a vector when restricted to a given surface, is lost in this process, but that might not be relevant for your needs.) If that works, then you can readily compute the vorticity using one of the routines in nek and store the result in a velocity field, then view that field with VisIt. Of course WSS will require multiplication by viscosity. hth, Paul ________________________________________ From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] Sent: Tuesday, January 21, 2014 10:33 AM To: nek5000-users at lists.mcs.anl.gov Subject: Re: [Nek5000-users] Pipe with expansion Hi paul, can I make this to be drag or shear quantities to be return to the a separate file so that it will easy for me to plot. By the way it gives the integral quantity. Think for example I need to find the shear stress on the wall from the inlet to outlet at a particular time = 2 . How can I do that ? Is there way to find the number of elements in x,y and z direction ? On 21/01/2014 17:32, nek5000-users at lists.mcs.anl.gov wrote: > > Hi Kamal, > > Your integrated drag quantities should be written to the logfile > (stdout), > assuming you've set the arguments in the call to be .true. > > Paul > > On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > >> Hi Paul, >> >> I checked the set_obj subroutine and implemented one in my .USR file. >> The code seem to run without any errors but I don't find where these >> variables are getting stored. >> >> I use VisIT to visualize my output, even there was no change in it. >> >> do I have to define my own output file and write the variables out ? >> >> Thanks, >> >> Kamal. >> >> >> On 20/01/2014 21:52, nek5000-users at lists.mcs.anl.gov wrote: >>> >>> Hi Kamal, >>> >>> You'll need to compute your own tke by manipulating the >>> velocity fields. >>> >>> You can get running averages of the requisite quantities >>> via calls to "avg_all" which is found in navier5.f >>> >>> You can compute shear stress on the wall simply by computing >>> the drag on the wall, which can be done via a call to torque_calc(), >>> also found in navier5.f >>> >>> If you cd to /examples and type: >>> >>> grep torq */*.usr >>> >>> you'll find many examples of calls to torque_calc. You simply >>> need to prescribe the surfaces on which shear is to be integrated. >>> >>> I typically write a routine "set_obj" to identify such surfaces >>> on the first call to usrchk. >>> >>> grep set_obj */*.usr >>> >>> will show similar examples. >>> >>> I would recommend trying this for laminar Poiseiulle flow in >>> a very simple channel just to check that your calls are properly >>> set. >>> >>> Best, >>> >>> Paul >>> >>> >>> On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>> >>>> Hi Paul, >>>> >>>> Thanks and that helped. >>>> >>>> Where can I find the variables like Turbulent KE , shear stress on >>>> the wall. ? >>>> >>>> Do i have to activate some parameters for calculating them ? >>>> >>>> If I had to plot them. >>>> >>>> Thanks, >>>> Kamal >>>> >>>> >>>> On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> >>>>> Kamal, >>>>> >>>>> Looks good. >>>>> >>>>> I'm guessing that one further refinement would be: >>>>> >>>>> if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) >>>>> if (z.gt.z1) scale = smax >>>>> >>>>> which would yield >>>>> >>>>> scale = 1 when z=z0 >>>>> scale = smax when z >= z1 >>>>> >>>>> Paul >>>>> >>>>> >>>>> >>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>>> Hi paul, >>>>>> >>>>>> The code works fine, but there should be a small change thats has >>>>>> to be done >>>>>> >>>>>> >>>>>> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >>>>>> if (z.gt.z1) scale = smax >>>>>> >>>>>> This creates a perfect diverging pipe. >>>>>> >>>>>> Thanks for the help paul. >>>>>> >>>>>> Kamal >>>>>> >>>>>> On Jan 20, 2014, at 12:09 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>>> Hi paul, >>>>>>> >>>>>>> If I am not wrong, >>>>>>> I make a mesh with three straight pipes( inlet, divergent, >>>>>>> outlet ) connected together via n2to3 so that I know the element >>>>>>> connectivity places of the divergent section (z0,z1) and use the >>>>>>> section what you gave >>>>>>> >>>>>>> Thank you for the code >>>>>>> >>>>>>> Kamal >>>>>>> >>>>>>> On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>>> >>>>>>>> Kamal, >>>>>>>> >>>>>>>> I would do the following in usrdat2(): >>>>>>>> >>>>>>>> n=nx1*ny1*nz1*nelt >>>>>>>> >>>>>>>> do i=1,n >>>>>>>> x=xm1(i,1,1,1) >>>>>>>> y=ym1(i,1,1,1) >>>>>>>> z=ym1(i,1,1,1) >>>>>>>> scale = 1. >>>>>>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>>>>>> if (z.gt.z1) scale = smax >>>>>>>> xm1(i,1,1,1) = scale*x >>>>>>>> ym1(i,1,1,1) = scale*y >>>>>>>> enddo >>>>>>>> >>>>>>>> Paul >>>>>>>> >>>>>>>> Make certain that z1 and z0 correspond to z values >>>>>>>> that precisely coincide with element interfaces. >>>>>>>> >>>>>>>> >>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> >>>>>>>>> Hi Paul, >>>>>>>>> >>>>>>>>> I looked into the Peris example but It is so what same like >>>>>>>>> the stenosis example with a Cosine deformation. >>>>>>>>> >>>>>>>>> In my case it is a pipe with conical divergent. I tried to >>>>>>>>> play around the variables Xm1, Ym1 and Zm1 but the mapping >>>>>>>>> doesn't go well. >>>>>>>>> >>>>>>>>> Could you please help me with this. >>>>>>>>> >>>>>>>>> Thank you, >>>>>>>>> >>>>>>>>> Kamal >>>>>>>>> >>>>>>>>> >>>>>>>>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>> wrote: >>>>>>>>> >>>>>>>>>> Hi Paul, >>>>>>>>>> >>>>>>>>>> I looked at the Helix and stenosis example but they are using >>>>>>>>>> cosine functions to deform >>>>>>>>>> >>>>>>>>>> I tried to use a tangent function but it bends the whole pipe. >>>>>>>>>> >>>>>>>>>> I dint look at peris example . >>>>>>>>>> >>>>>>>>>> I will take a look at it and let you know. >>>>>>>>>> >>>>>>>>>> Thank you >>>>>>>>>> >>>>>>>>>> Kamal >>>>>>>>>> >>>>>>>>>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>> wrote: >>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> Kamal, >>>>>>>>>>> >>>>>>>>>>> Have you looked at the peris example? The usr file there >>>>>>>>>>> shows how to deform >>>>>>>>>>> a pipe geometry. >>>>>>>>>>> >>>>>>>>>>> Paul >>>>>>>>>>> >>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>>>>>> >>>>>>>>>>> Dear Paul, >>>>>>>>>>> >>>>>>>>>>> I tried many ways to map my straight pipe geometry but it >>>>>>>>>>> does not seem to work properly >>>>>>>>>>> >>>>>>>>>>> I used something like >>>>>>>>>>> >>>>>>>>>>> X = X + Z * tan ( alpha ) >>>>>>>>>>> Y = Y + Z* tan (alpha ) >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> even that dint work. could please help me with this >>>>>>>>>>> >>>>>>>>>>> Thank you >>>>>>>>>>> >>>>>>>>>>> Kamal. >>>>>>>>>>> >>>>>>>>>>> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> wrote: >>>>>>>>>>> >>>>>>>>>>>> Hi Paul, >>>>>>>>>>>> >>>>>>>>>>>> Thanks paul. I tried working with the diverging mesh >>>>>>>>>>>> modification. >>>>>>>>>>>> >>>>>>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>>>>>> >>>>>>>>>>>> z = mx + b >>>>>>>>>>>> z = ny + c >>>>>>>>>>>> >>>>>>>>>>>> x = ( z - b ) / m >>>>>>>>>>>> y = (z - c) / n >>>>>>>>>>>> >>>>>>>>>>>> Do you think would work ? or is there any other way to >>>>>>>>>>>> input that ? >>>>>>>>>>>> >>>>>>>>>>>> Thanks, >>>>>>>>>>>> >>>>>>>>>>>> Kamal >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>>>>>> Kamal, >>>>>>>>>>>>> >>>>>>>>>>>>> 1) To check for convergence, run your simulation for >>>>>>>>>>>>> increasing polynomial orders ( lx1 in the SIZE file) and >>>>>>>>>>>>> measure some consistent quantity (drag, TKE, etc). You >>>>>>>>>>>>> can plot this quantity against lx1 and this should give >>>>>>>>>>>>> you a good picture of how you are converging (without >>>>>>>>>>>>> needing to change the physical mesh). >>>>>>>>>>>>> >>>>>>>>>>>>> 2) If you weren't using temperature in your simulation, >>>>>>>>>>>>> you could do put the following code snippet in your userchk >>>>>>>>>>>>> >>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>> integer i, ntot >>>>>>>>>>>>> >>>>>>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in >>>>>>>>>>>>> simulation (on THIS processor) >>>>>>>>>>>>> >>>>>>>>>>>>> do i = 1,ntot >>>>>>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + >>>>>>>>>>>>> vz(i,1,1,1)**2) >>>>>>>>>>>>> enddo >>>>>>>>>>>>> >>>>>>>>>>>>> ifto = .true. >>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>> >>>>>>>>>>>>> I've assumed here that your density is unity. This >>>>>>>>>>>>> computed kinetic energy point-wise and stores it in the >>>>>>>>>>>>> temperature field. The part "ifto = .true." tells Nek to >>>>>>>>>>>>> output the temperature field whenever it outputs a field >>>>>>>>>>>>> file. You could then view this in visit just like you >>>>>>>>>>>>> would the velocity field. >>>>>>>>>>>>> >>>>>>>>>>>>> Hope this helps! >>>>>>>>>>>>> >>>>>>>>>>>>> Josh >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, >>>>>>>>>>>>> wrote: >>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>> >>>>>>>>>>>>> I will try that mapping, I created a straight pipe to do >>>>>>>>>>>>> some simulations. >>>>>>>>>>>>> >>>>>>>>>>>>> 1) Is there a way to check my spectral convergence, so >>>>>>>>>>>>> that I can do some mesh convergence study? >>>>>>>>>>>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>>>>>>>>>>> >>>>>>>>>>>>> Thank you, >>>>>>>>>>>>> Kamal >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>> >>>>>>>>>>>>> Hi Kamal, >>>>>>>>>>>>> >>>>>>>>>>>>> For the geometry you describe, I would apply mesh morphing >>>>>>>>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>>>>>>>> using a subset of the mkmesh script provided in the expansion >>>>>>>>>>>>> example. >>>>>>>>>>>>> >>>>>>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>>>>>> certain that the change in slope occurs at element >>>>>>>>>>>>> boundaries, >>>>>>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>>>>>> >>>>>>>>>>>>> _______________ >>>>>>>>>>>>> /| | | >>>>>>>>>>>>> / | | | >>>>>>>>>>>>> /| | | | >>>>>>>>>>>>> ________________/ | | | | >>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> Paul >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>> >>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>> >>>>>>>>>>>>> I looked at the example and it looks very helpful, but for >>>>>>>>>>>>> a sudden expansion we have only two parts (i.e) the inlet >>>>>>>>>>>>> pipe and the outlet pipe. Whereas in a diverging pipe we >>>>>>>>>>>>> have three section (i.e,) The inlet pipe, Diverging >>>>>>>>>>>>> section and the outlet pipe. >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> Is it possible for me to create a 2D diverging section >>>>>>>>>>>>> using mesh modification and revolve it around the centre >>>>>>>>>>>>> axis to get a 3d diverging pipe ? >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> or should I apply the mesh modification directly to the 3d >>>>>>>>>>>>> sudden expansion pipe using usrdat2() ? >>>>>>>>>>>>> >>>>>>>>>>>>> Thanks, >>>>>>>>>>>>> Kamal >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>> >>>>>>>>>>>>> Thanks a lot for the update. I will take a look at as soon >>>>>>>>>>>>> as possible and keep you updated with it. >>>>>>>>>>>>> >>>>>>>>>>>>> Thank you, >>>>>>>>>>>>> >>>>>>>>>>>>> Kamal >>>>>>>>>>>>> >>>>>>>>>>>>> On Jan 14, 2014, at 9:04 PM, >>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>> >>>>>>>>>>>>> Kamal, >>>>>>>>>>>>> >>>>>>>>>>>>> I've added an example for a step-type expansion in a pipe. >>>>>>>>>>>>> New example directory >>>>>>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>>>>>> >>>>>>>>>>>>> If you want a standard diffuser, I would use >>>>>>>>>>>>> mesh-morphing, as outlined in the >>>>>>>>>>>>> nek primer, which can be found on this page: >>>>>>>>>>>>> >>>>>>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>>>>>> >>>>>>>>>>>>> I've also automated our turbulent outflow bc treatment -- >>>>>>>>>>>>> one simply provides an >>>>>>>>>>>>> expansion factor (typically ~ 1.5) and two persistent >>>>>>>>>>>>> arrays to turb_outflow(), which >>>>>>>>>>>>> is now in navier5.f. This can be useful when very >>>>>>>>>>>>> strong vortices are leaving the >>>>>>>>>>>>> domain, which is possible for certain diffuser flow >>>>>>>>>>>>> conditions (and others). >>>>>>>>>>>>> >>>>>>>>>>>>> Paul >>>>>>>>>>>>> ________________________________________ >>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf >>>>>>>>>>>>> ofnek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>>>>>> >>>>>>>>>>>>> Hi >>>>>>>>>>>>> >>>>>>>>>>>>> Can some one please help me in this because I am new to nek >>>>>>>>>>>>> >>>>>>>>>>>>> 1) How can I create a .rea for a specific geometry say ' A >>>>>>>>>>>>> sudden >>>>>>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>>>>>> >>>>>>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> Thank you >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> kamal >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> -- >>>>>>>>>>>>> Josh Camp >>>>>>>>>>>>> >>>>>>>>>>>>> "All that is necessary for the triumph of evil is that >>>>>>>>>>>>> good men do nothing" -- Edmund Burke >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> >>>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users _______________________________________________ Nek5000-users mailing list Nek5000-users at lists.mcs.anl.gov https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users From nek5000-users at lists.mcs.anl.gov Wed Jan 22 09:37:39 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Wed, 22 Jan 2014 16:37:39 +0100 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , , Message-ID: Hello Paul I was thinking about taking the tangential velocity near to the wall so that I can figure out my length of the recirculation region. Is it possible for me to access the boundary elements of the mesh ??? so that I can take the boundary element and then obtain the velocity at that point so that I can figure out the length of my recirculation region. or take the *.fld file and read it to plot the datas I need. I also want to calculate the axial viscous force acting on the entire pipe. which is given by C_v = F^v / ( d^2 * rho * U^2 ) = double integral ( 1/Re * (du / dr) ) dtheta dz On Jan 22, 2014, at 4:07 PM, nek5000-users at lists.mcs.anl.gov wrote: > > Hi Kamal, > > As I thought about it some more, if you're interested in the local wall shear stress > magnitude I'm quite certain you can get this by plotting the magnitude of vorticity > on the surface in question. (Note that the sign of the WSS, which in fact is a tensor > or a vector when restricted to a given surface, is lost in this process, but that might > not be relevant for your needs.) If that works, then you can readily compute the > vorticity using one of the routines in nek and store the result in a velocity field, then > view that field with VisIt. Of course WSS will require multiplication by viscosity. > > hth, > > Paul > > ________________________________________ > From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] > Sent: Tuesday, January 21, 2014 10:33 AM > To: nek5000-users at lists.mcs.anl.gov > Subject: Re: [Nek5000-users] Pipe with expansion > > Hi paul, > > can I make this to be drag or shear quantities to be return to the a > separate file so that it will easy for me to plot. > > By the way it gives the integral quantity. Think for example I need to > find the shear stress on the wall from the inlet to outlet at a > particular time = 2 . How can I do that ? > > Is there way to find the number of elements in x,y and z direction ? > > On 21/01/2014 17:32, nek5000-users at lists.mcs.anl.gov wrote: >> >> Hi Kamal, >> >> Your integrated drag quantities should be written to the logfile >> (stdout), >> assuming you've set the arguments in the call to be .true. >> >> Paul >> >> On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >> >>> Hi Paul, >>> >>> I checked the set_obj subroutine and implemented one in my .USR file. >>> The code seem to run without any errors but I don't find where these >>> variables are getting stored. >>> >>> I use VisIT to visualize my output, even there was no change in it. >>> >>> do I have to define my own output file and write the variables out ? >>> >>> Thanks, >>> >>> Kamal. >>> >>> >>> On 20/01/2014 21:52, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>> Hi Kamal, >>>> >>>> You'll need to compute your own tke by manipulating the >>>> velocity fields. >>>> >>>> You can get running averages of the requisite quantities >>>> via calls to "avg_all" which is found in navier5.f >>>> >>>> You can compute shear stress on the wall simply by computing >>>> the drag on the wall, which can be done via a call to torque_calc(), >>>> also found in navier5.f >>>> >>>> If you cd to /examples and type: >>>> >>>> grep torq */*.usr >>>> >>>> you'll find many examples of calls to torque_calc. You simply >>>> need to prescribe the surfaces on which shear is to be integrated. >>>> >>>> I typically write a routine "set_obj" to identify such surfaces >>>> on the first call to usrchk. >>>> >>>> grep set_obj */*.usr >>>> >>>> will show similar examples. >>>> >>>> I would recommend trying this for laminar Poiseiulle flow in >>>> a very simple channel just to check that your calls are properly >>>> set. >>>> >>>> Best, >>>> >>>> Paul >>>> >>>> >>>> On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> Hi Paul, >>>>> >>>>> Thanks and that helped. >>>>> >>>>> Where can I find the variables like Turbulent KE , shear stress on >>>>> the wall. ? >>>>> >>>>> Do i have to activate some parameters for calculating them ? >>>>> >>>>> If I had to plot them. >>>>> >>>>> Thanks, >>>>> Kamal >>>>> >>>>> >>>>> On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>>> >>>>>> Kamal, >>>>>> >>>>>> Looks good. >>>>>> >>>>>> I'm guessing that one further refinement would be: >>>>>> >>>>>> if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) >>>>>> if (z.gt.z1) scale = smax >>>>>> >>>>>> which would yield >>>>>> >>>>>> scale = 1 when z=z0 >>>>>> scale = smax when z >= z1 >>>>>> >>>>>> Paul >>>>>> >>>>>> >>>>>> >>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>>> Hi paul, >>>>>>> >>>>>>> The code works fine, but there should be a small change thats has >>>>>>> to be done >>>>>>> >>>>>>> >>>>>>> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >>>>>>> if (z.gt.z1) scale = smax >>>>>>> >>>>>>> This creates a perfect diverging pipe. >>>>>>> >>>>>>> Thanks for the help paul. >>>>>>> >>>>>>> Kamal >>>>>>> >>>>>>> On Jan 20, 2014, at 12:09 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>>> Hi paul, >>>>>>>> >>>>>>>> If I am not wrong, >>>>>>>> I make a mesh with three straight pipes( inlet, divergent, >>>>>>>> outlet ) connected together via n2to3 so that I know the element >>>>>>>> connectivity places of the divergent section (z0,z1) and use the >>>>>>>> section what you gave >>>>>>>> >>>>>>>> Thank you for the code >>>>>>>> >>>>>>>> Kamal >>>>>>>> >>>>>>>> On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> >>>>>>>>> >>>>>>>>> Kamal, >>>>>>>>> >>>>>>>>> I would do the following in usrdat2(): >>>>>>>>> >>>>>>>>> n=nx1*ny1*nz1*nelt >>>>>>>>> >>>>>>>>> do i=1,n >>>>>>>>> x=xm1(i,1,1,1) >>>>>>>>> y=ym1(i,1,1,1) >>>>>>>>> z=ym1(i,1,1,1) >>>>>>>>> scale = 1. >>>>>>>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>> xm1(i,1,1,1) = scale*x >>>>>>>>> ym1(i,1,1,1) = scale*y >>>>>>>>> enddo >>>>>>>>> >>>>>>>>> Paul >>>>>>>>> >>>>>>>>> Make certain that z1 and z0 correspond to z values >>>>>>>>> that precisely coincide with element interfaces. >>>>>>>>> >>>>>>>>> >>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>> >>>>>>>>>> Hi Paul, >>>>>>>>>> >>>>>>>>>> I looked into the Peris example but It is so what same like >>>>>>>>>> the stenosis example with a Cosine deformation. >>>>>>>>>> >>>>>>>>>> In my case it is a pipe with conical divergent. I tried to >>>>>>>>>> play around the variables Xm1, Ym1 and Zm1 but the mapping >>>>>>>>>> doesn't go well. >>>>>>>>>> >>>>>>>>>> Could you please help me with this. >>>>>>>>>> >>>>>>>>>> Thank you, >>>>>>>>>> >>>>>>>>>> Kamal >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>> wrote: >>>>>>>>>> >>>>>>>>>>> Hi Paul, >>>>>>>>>>> >>>>>>>>>>> I looked at the Helix and stenosis example but they are using >>>>>>>>>>> cosine functions to deform >>>>>>>>>>> >>>>>>>>>>> I tried to use a tangent function but it bends the whole pipe. >>>>>>>>>>> >>>>>>>>>>> I dint look at peris example . >>>>>>>>>>> >>>>>>>>>>> I will take a look at it and let you know. >>>>>>>>>>> >>>>>>>>>>> Thank you >>>>>>>>>>> >>>>>>>>>>> Kamal >>>>>>>>>>> >>>>>>>>>>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> wrote: >>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> Kamal, >>>>>>>>>>>> >>>>>>>>>>>> Have you looked at the peris example? The usr file there >>>>>>>>>>>> shows how to deform >>>>>>>>>>>> a pipe geometry. >>>>>>>>>>>> >>>>>>>>>>>> Paul >>>>>>>>>>>> >>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>>>>>>> >>>>>>>>>>>> Dear Paul, >>>>>>>>>>>> >>>>>>>>>>>> I tried many ways to map my straight pipe geometry but it >>>>>>>>>>>> does not seem to work properly >>>>>>>>>>>> >>>>>>>>>>>> I used something like >>>>>>>>>>>> >>>>>>>>>>>> X = X + Z * tan ( alpha ) >>>>>>>>>>>> Y = Y + Z* tan (alpha ) >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> even that dint work. could please help me with this >>>>>>>>>>>> >>>>>>>>>>>> Thank you >>>>>>>>>>>> >>>>>>>>>>>> Kamal. >>>>>>>>>>>> >>>>>>>>>>>> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> wrote: >>>>>>>>>>>> >>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>> >>>>>>>>>>>>> Thanks paul. I tried working with the diverging mesh >>>>>>>>>>>>> modification. >>>>>>>>>>>>> >>>>>>>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>>>>>>> >>>>>>>>>>>>> z = mx + b >>>>>>>>>>>>> z = ny + c >>>>>>>>>>>>> >>>>>>>>>>>>> x = ( z - b ) / m >>>>>>>>>>>>> y = (z - c) / n >>>>>>>>>>>>> >>>>>>>>>>>>> Do you think would work ? or is there any other way to >>>>>>>>>>>>> input that ? >>>>>>>>>>>>> >>>>>>>>>>>>> Thanks, >>>>>>>>>>>>> >>>>>>>>>>>>> Kamal >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>> >>>>>>>>>>>>>> 1) To check for convergence, run your simulation for >>>>>>>>>>>>>> increasing polynomial orders ( lx1 in the SIZE file) and >>>>>>>>>>>>>> measure some consistent quantity (drag, TKE, etc). You >>>>>>>>>>>>>> can plot this quantity against lx1 and this should give >>>>>>>>>>>>>> you a good picture of how you are converging (without >>>>>>>>>>>>>> needing to change the physical mesh). >>>>>>>>>>>>>> >>>>>>>>>>>>>> 2) If you weren't using temperature in your simulation, >>>>>>>>>>>>>> you could do put the following code snippet in your userchk >>>>>>>>>>>>>> >>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>> integer i, ntot >>>>>>>>>>>>>> >>>>>>>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in >>>>>>>>>>>>>> simulation (on THIS processor) >>>>>>>>>>>>>> >>>>>>>>>>>>>> do i = 1,ntot >>>>>>>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + >>>>>>>>>>>>>> vz(i,1,1,1)**2) >>>>>>>>>>>>>> enddo >>>>>>>>>>>>>> >>>>>>>>>>>>>> ifto = .true. >>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>> >>>>>>>>>>>>>> I've assumed here that your density is unity. This >>>>>>>>>>>>>> computed kinetic energy point-wise and stores it in the >>>>>>>>>>>>>> temperature field. The part "ifto = .true." tells Nek to >>>>>>>>>>>>>> output the temperature field whenever it outputs a field >>>>>>>>>>>>>> file. You could then view this in visit just like you >>>>>>>>>>>>>> would the velocity field. >>>>>>>>>>>>>> >>>>>>>>>>>>>> Hope this helps! >>>>>>>>>>>>>> >>>>>>>>>>>>>> Josh >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, >>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> I will try that mapping, I created a straight pipe to do >>>>>>>>>>>>>> some simulations. >>>>>>>>>>>>>> >>>>>>>>>>>>>> 1) Is there a way to check my spectral convergence, so >>>>>>>>>>>>>> that I can do some mesh convergence study? >>>>>>>>>>>>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>> Hi Kamal, >>>>>>>>>>>>>> >>>>>>>>>>>>>> For the geometry you describe, I would apply mesh morphing >>>>>>>>>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>>>>>>>>> using a subset of the mkmesh script provided in the expansion >>>>>>>>>>>>>> example. >>>>>>>>>>>>>> >>>>>>>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>>>>>>> certain that the change in slope occurs at element >>>>>>>>>>>>>> boundaries, >>>>>>>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________ >>>>>>>>>>>>>> /| | | >>>>>>>>>>>>>> / | | | >>>>>>>>>>>>>> /| | | | >>>>>>>>>>>>>> ________________/ | | | | >>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> Paul >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> I looked at the example and it looks very helpful, but for >>>>>>>>>>>>>> a sudden expansion we have only two parts (i.e) the inlet >>>>>>>>>>>>>> pipe and the outlet pipe. Whereas in a diverging pipe we >>>>>>>>>>>>>> have three section (i.e,) The inlet pipe, Diverging >>>>>>>>>>>>>> section and the outlet pipe. >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> Is it possible for me to create a 2D diverging section >>>>>>>>>>>>>> using mesh modification and revolve it around the centre >>>>>>>>>>>>>> axis to get a 3d diverging pipe ? >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> or should I apply the mesh modification directly to the 3d >>>>>>>>>>>>>> sudden expansion pipe using usrdat2() ? >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thanks a lot for the update. I will take a look at as soon >>>>>>>>>>>>>> as possible and keep you updated with it. >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Jan 14, 2014, at 9:04 PM, >>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>> >>>>>>>>>>>>>> I've added an example for a step-type expansion in a pipe. >>>>>>>>>>>>>> New example directory >>>>>>>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>>>>>>> >>>>>>>>>>>>>> If you want a standard diffuser, I would use >>>>>>>>>>>>>> mesh-morphing, as outlined in the >>>>>>>>>>>>>> nek primer, which can be found on this page: >>>>>>>>>>>>>> >>>>>>>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>>>>>>> >>>>>>>>>>>>>> I've also automated our turbulent outflow bc treatment -- >>>>>>>>>>>>>> one simply provides an >>>>>>>>>>>>>> expansion factor (typically ~ 1.5) and two persistent >>>>>>>>>>>>>> arrays to turb_outflow(), which >>>>>>>>>>>>>> is now in navier5.f. This can be useful when very >>>>>>>>>>>>>> strong vortices are leaving the >>>>>>>>>>>>>> domain, which is possible for certain diffuser flow >>>>>>>>>>>>>> conditions (and others). >>>>>>>>>>>>>> >>>>>>>>>>>>>> Paul >>>>>>>>>>>>>> ________________________________________ >>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf >>>>>>>>>>>>>> ofnek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>>>>>>> >>>>>>>>>>>>>> Hi >>>>>>>>>>>>>> >>>>>>>>>>>>>> Can some one please help me in this because I am new to nek >>>>>>>>>>>>>> >>>>>>>>>>>>>> 1) How can I create a .rea for a specific geometry say ' A >>>>>>>>>>>>>> sudden >>>>>>>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>>>>>>> >>>>>>>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> kamal >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> -- >>>>>>>>>>>>>> Josh Camp >>>>>>>>>>>>>> >>>>>>>>>>>>>> "All that is necessary for the triumph of evil is that >>>>>>>>>>>>>> good men do nothing" -- Edmund Burke >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> >>>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users From nek5000-users at lists.mcs.anl.gov Wed Jan 22 09:39:12 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Wed, 22 Jan 2014 15:39:12 +0000 Subject: [Nek5000-users] Postdoc position available - Please post to the list In-Reply-To: Message-ID: Prof. Mavriplis and the University of Ottawa are currently looking for a postdoctoral researcher interested in pursuing research in the field of Computational Fluid Dynamics (CFD). The main topic of research will be adaptive discontinuous Galerkin or spectral element methods for direct simulation (incompressible Navier-Stokes equations), and other projects may include control of separated flows, transition, aerodynamics and CFD for blood flow. A PhD degree in CFD or Fluid Dynamics including code development and high performance computing is necessary. The candidate must have already published journal articles. Experience with spectral methods, Nek5000, and VISIT is a plus. The ideal candidate will have excellent computer programming skills, communication skills (written, oral, graphical and with others in the research group), self-motivation and an open mind. The position also requires some training of graduate students. Please send a short email with cv attached by email with 'Nek5000 Postdoc application' in the subject line. Ideally this would be for the immediate timeframe. The position is at University of Ottawa in Ottawa, Canada. Please send a short email with cv attached by email with 'Nek5000 PhD application' in the subject line. Catherine Mavriplis http://www.engineering.uottawa.ca/en/directory/view/mavriplis_catherine -- Prof. Catherine Mavriplis Dept. of Mechanical Engineering / G?nie m?canique University of Ottawa / Universit? d'Ottawa 161 Louis Pasteur Room A331 Ottawa, Ontario CANADA K1N 6N5 -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Wed Jan 22 09:53:42 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Wed, 22 Jan 2014 15:53:42 +0000 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , , , Message-ID: Axial viscous stress is given by torq_calc -- that's no problem whatsoever. You get a number as a function of time. You can even get stresses on multiple subsets of the geometry (e.g., if you had multiple branches in the domain or multiple cylinders. The drag, which is a byproduct of the torque computation (which you can ignore), is given in terms of the viscous and pressure components separately and as the sum of the two. You can identify domain boundaries by checking the boundary conditions. Here, I recommend looking at the set_obj routines in several of the /example cases. ________________________________________ From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] Sent: Wednesday, January 22, 2014 9:37 AM To: nek5000-users at lists.mcs.anl.gov Subject: Re: [Nek5000-users] Pipe with expansion Hello Paul I was thinking about taking the tangential velocity near to the wall so that I can figure out my length of the recirculation region. Is it possible for me to access the boundary elements of the mesh ??? so that I can take the boundary element and then obtain the velocity at that point so that I can figure out the length of my recirculation region. or take the *.fld file and read it to plot the datas I need. I also want to calculate the axial viscous force acting on the entire pipe. which is given by C_v = F^v / ( d^2 * rho * U^2 ) = double integral ( 1/Re * (du / dr) ) dtheta dz On Jan 22, 2014, at 4:07 PM, nek5000-users at lists.mcs.anl.gov wrote: > > Hi Kamal, > > As I thought about it some more, if you're interested in the local wall shear stress > magnitude I'm quite certain you can get this by plotting the magnitude of vorticity > on the surface in question. (Note that the sign of the WSS, which in fact is a tensor > or a vector when restricted to a given surface, is lost in this process, but that might > not be relevant for your needs.) If that works, then you can readily compute the > vorticity using one of the routines in nek and store the result in a velocity field, then > view that field with VisIt. Of course WSS will require multiplication by viscosity. > > hth, > > Paul > > ________________________________________ > From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] > Sent: Tuesday, January 21, 2014 10:33 AM > To: nek5000-users at lists.mcs.anl.gov > Subject: Re: [Nek5000-users] Pipe with expansion > > Hi paul, > > can I make this to be drag or shear quantities to be return to the a > separate file so that it will easy for me to plot. > > By the way it gives the integral quantity. Think for example I need to > find the shear stress on the wall from the inlet to outlet at a > particular time = 2 . How can I do that ? > > Is there way to find the number of elements in x,y and z direction ? > > On 21/01/2014 17:32, nek5000-users at lists.mcs.anl.gov wrote: >> >> Hi Kamal, >> >> Your integrated drag quantities should be written to the logfile >> (stdout), >> assuming you've set the arguments in the call to be .true. >> >> Paul >> >> On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >> >>> Hi Paul, >>> >>> I checked the set_obj subroutine and implemented one in my .USR file. >>> The code seem to run without any errors but I don't find where these >>> variables are getting stored. >>> >>> I use VisIT to visualize my output, even there was no change in it. >>> >>> do I have to define my own output file and write the variables out ? >>> >>> Thanks, >>> >>> Kamal. >>> >>> >>> On 20/01/2014 21:52, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>> Hi Kamal, >>>> >>>> You'll need to compute your own tke by manipulating the >>>> velocity fields. >>>> >>>> You can get running averages of the requisite quantities >>>> via calls to "avg_all" which is found in navier5.f >>>> >>>> You can compute shear stress on the wall simply by computing >>>> the drag on the wall, which can be done via a call to torque_calc(), >>>> also found in navier5.f >>>> >>>> If you cd to /examples and type: >>>> >>>> grep torq */*.usr >>>> >>>> you'll find many examples of calls to torque_calc. You simply >>>> need to prescribe the surfaces on which shear is to be integrated. >>>> >>>> I typically write a routine "set_obj" to identify such surfaces >>>> on the first call to usrchk. >>>> >>>> grep set_obj */*.usr >>>> >>>> will show similar examples. >>>> >>>> I would recommend trying this for laminar Poiseiulle flow in >>>> a very simple channel just to check that your calls are properly >>>> set. >>>> >>>> Best, >>>> >>>> Paul >>>> >>>> >>>> On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> Hi Paul, >>>>> >>>>> Thanks and that helped. >>>>> >>>>> Where can I find the variables like Turbulent KE , shear stress on >>>>> the wall. ? >>>>> >>>>> Do i have to activate some parameters for calculating them ? >>>>> >>>>> If I had to plot them. >>>>> >>>>> Thanks, >>>>> Kamal >>>>> >>>>> >>>>> On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>>> >>>>>> Kamal, >>>>>> >>>>>> Looks good. >>>>>> >>>>>> I'm guessing that one further refinement would be: >>>>>> >>>>>> if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) >>>>>> if (z.gt.z1) scale = smax >>>>>> >>>>>> which would yield >>>>>> >>>>>> scale = 1 when z=z0 >>>>>> scale = smax when z >= z1 >>>>>> >>>>>> Paul >>>>>> >>>>>> >>>>>> >>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>>> Hi paul, >>>>>>> >>>>>>> The code works fine, but there should be a small change thats has >>>>>>> to be done >>>>>>> >>>>>>> >>>>>>> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >>>>>>> if (z.gt.z1) scale = smax >>>>>>> >>>>>>> This creates a perfect diverging pipe. >>>>>>> >>>>>>> Thanks for the help paul. >>>>>>> >>>>>>> Kamal >>>>>>> >>>>>>> On Jan 20, 2014, at 12:09 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>>> Hi paul, >>>>>>>> >>>>>>>> If I am not wrong, >>>>>>>> I make a mesh with three straight pipes( inlet, divergent, >>>>>>>> outlet ) connected together via n2to3 so that I know the element >>>>>>>> connectivity places of the divergent section (z0,z1) and use the >>>>>>>> section what you gave >>>>>>>> >>>>>>>> Thank you for the code >>>>>>>> >>>>>>>> Kamal >>>>>>>> >>>>>>>> On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> >>>>>>>>> >>>>>>>>> Kamal, >>>>>>>>> >>>>>>>>> I would do the following in usrdat2(): >>>>>>>>> >>>>>>>>> n=nx1*ny1*nz1*nelt >>>>>>>>> >>>>>>>>> do i=1,n >>>>>>>>> x=xm1(i,1,1,1) >>>>>>>>> y=ym1(i,1,1,1) >>>>>>>>> z=ym1(i,1,1,1) >>>>>>>>> scale = 1. >>>>>>>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>> xm1(i,1,1,1) = scale*x >>>>>>>>> ym1(i,1,1,1) = scale*y >>>>>>>>> enddo >>>>>>>>> >>>>>>>>> Paul >>>>>>>>> >>>>>>>>> Make certain that z1 and z0 correspond to z values >>>>>>>>> that precisely coincide with element interfaces. >>>>>>>>> >>>>>>>>> >>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>> >>>>>>>>>> Hi Paul, >>>>>>>>>> >>>>>>>>>> I looked into the Peris example but It is so what same like >>>>>>>>>> the stenosis example with a Cosine deformation. >>>>>>>>>> >>>>>>>>>> In my case it is a pipe with conical divergent. I tried to >>>>>>>>>> play around the variables Xm1, Ym1 and Zm1 but the mapping >>>>>>>>>> doesn't go well. >>>>>>>>>> >>>>>>>>>> Could you please help me with this. >>>>>>>>>> >>>>>>>>>> Thank you, >>>>>>>>>> >>>>>>>>>> Kamal >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>> wrote: >>>>>>>>>> >>>>>>>>>>> Hi Paul, >>>>>>>>>>> >>>>>>>>>>> I looked at the Helix and stenosis example but they are using >>>>>>>>>>> cosine functions to deform >>>>>>>>>>> >>>>>>>>>>> I tried to use a tangent function but it bends the whole pipe. >>>>>>>>>>> >>>>>>>>>>> I dint look at peris example . >>>>>>>>>>> >>>>>>>>>>> I will take a look at it and let you know. >>>>>>>>>>> >>>>>>>>>>> Thank you >>>>>>>>>>> >>>>>>>>>>> Kamal >>>>>>>>>>> >>>>>>>>>>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> wrote: >>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> Kamal, >>>>>>>>>>>> >>>>>>>>>>>> Have you looked at the peris example? The usr file there >>>>>>>>>>>> shows how to deform >>>>>>>>>>>> a pipe geometry. >>>>>>>>>>>> >>>>>>>>>>>> Paul >>>>>>>>>>>> >>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>>>>>>> >>>>>>>>>>>> Dear Paul, >>>>>>>>>>>> >>>>>>>>>>>> I tried many ways to map my straight pipe geometry but it >>>>>>>>>>>> does not seem to work properly >>>>>>>>>>>> >>>>>>>>>>>> I used something like >>>>>>>>>>>> >>>>>>>>>>>> X = X + Z * tan ( alpha ) >>>>>>>>>>>> Y = Y + Z* tan (alpha ) >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> even that dint work. could please help me with this >>>>>>>>>>>> >>>>>>>>>>>> Thank you >>>>>>>>>>>> >>>>>>>>>>>> Kamal. >>>>>>>>>>>> >>>>>>>>>>>> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> wrote: >>>>>>>>>>>> >>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>> >>>>>>>>>>>>> Thanks paul. I tried working with the diverging mesh >>>>>>>>>>>>> modification. >>>>>>>>>>>>> >>>>>>>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>>>>>>> >>>>>>>>>>>>> z = mx + b >>>>>>>>>>>>> z = ny + c >>>>>>>>>>>>> >>>>>>>>>>>>> x = ( z - b ) / m >>>>>>>>>>>>> y = (z - c) / n >>>>>>>>>>>>> >>>>>>>>>>>>> Do you think would work ? or is there any other way to >>>>>>>>>>>>> input that ? >>>>>>>>>>>>> >>>>>>>>>>>>> Thanks, >>>>>>>>>>>>> >>>>>>>>>>>>> Kamal >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>> >>>>>>>>>>>>>> 1) To check for convergence, run your simulation for >>>>>>>>>>>>>> increasing polynomial orders ( lx1 in the SIZE file) and >>>>>>>>>>>>>> measure some consistent quantity (drag, TKE, etc). You >>>>>>>>>>>>>> can plot this quantity against lx1 and this should give >>>>>>>>>>>>>> you a good picture of how you are converging (without >>>>>>>>>>>>>> needing to change the physical mesh). >>>>>>>>>>>>>> >>>>>>>>>>>>>> 2) If you weren't using temperature in your simulation, >>>>>>>>>>>>>> you could do put the following code snippet in your userchk >>>>>>>>>>>>>> >>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>> integer i, ntot >>>>>>>>>>>>>> >>>>>>>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in >>>>>>>>>>>>>> simulation (on THIS processor) >>>>>>>>>>>>>> >>>>>>>>>>>>>> do i = 1,ntot >>>>>>>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + >>>>>>>>>>>>>> vz(i,1,1,1)**2) >>>>>>>>>>>>>> enddo >>>>>>>>>>>>>> >>>>>>>>>>>>>> ifto = .true. >>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>> >>>>>>>>>>>>>> I've assumed here that your density is unity. This >>>>>>>>>>>>>> computed kinetic energy point-wise and stores it in the >>>>>>>>>>>>>> temperature field. The part "ifto = .true." tells Nek to >>>>>>>>>>>>>> output the temperature field whenever it outputs a field >>>>>>>>>>>>>> file. You could then view this in visit just like you >>>>>>>>>>>>>> would the velocity field. >>>>>>>>>>>>>> >>>>>>>>>>>>>> Hope this helps! >>>>>>>>>>>>>> >>>>>>>>>>>>>> Josh >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, >>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> I will try that mapping, I created a straight pipe to do >>>>>>>>>>>>>> some simulations. >>>>>>>>>>>>>> >>>>>>>>>>>>>> 1) Is there a way to check my spectral convergence, so >>>>>>>>>>>>>> that I can do some mesh convergence study? >>>>>>>>>>>>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>> Hi Kamal, >>>>>>>>>>>>>> >>>>>>>>>>>>>> For the geometry you describe, I would apply mesh morphing >>>>>>>>>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>>>>>>>>> using a subset of the mkmesh script provided in the expansion >>>>>>>>>>>>>> example. >>>>>>>>>>>>>> >>>>>>>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>>>>>>> certain that the change in slope occurs at element >>>>>>>>>>>>>> boundaries, >>>>>>>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________ >>>>>>>>>>>>>> /| | | >>>>>>>>>>>>>> / | | | >>>>>>>>>>>>>> /| | | | >>>>>>>>>>>>>> ________________/ | | | | >>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> Paul >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> I looked at the example and it looks very helpful, but for >>>>>>>>>>>>>> a sudden expansion we have only two parts (i.e) the inlet >>>>>>>>>>>>>> pipe and the outlet pipe. Whereas in a diverging pipe we >>>>>>>>>>>>>> have three section (i.e,) The inlet pipe, Diverging >>>>>>>>>>>>>> section and the outlet pipe. >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> Is it possible for me to create a 2D diverging section >>>>>>>>>>>>>> using mesh modification and revolve it around the centre >>>>>>>>>>>>>> axis to get a 3d diverging pipe ? >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> or should I apply the mesh modification directly to the 3d >>>>>>>>>>>>>> sudden expansion pipe using usrdat2() ? >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thanks a lot for the update. I will take a look at as soon >>>>>>>>>>>>>> as possible and keep you updated with it. >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Jan 14, 2014, at 9:04 PM, >>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>> >>>>>>>>>>>>>> I've added an example for a step-type expansion in a pipe. >>>>>>>>>>>>>> New example directory >>>>>>>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>>>>>>> >>>>>>>>>>>>>> If you want a standard diffuser, I would use >>>>>>>>>>>>>> mesh-morphing, as outlined in the >>>>>>>>>>>>>> nek primer, which can be found on this page: >>>>>>>>>>>>>> >>>>>>>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>>>>>>> >>>>>>>>>>>>>> I've also automated our turbulent outflow bc treatment -- >>>>>>>>>>>>>> one simply provides an >>>>>>>>>>>>>> expansion factor (typically ~ 1.5) and two persistent >>>>>>>>>>>>>> arrays to turb_outflow(), which >>>>>>>>>>>>>> is now in navier5.f. This can be useful when very >>>>>>>>>>>>>> strong vortices are leaving the >>>>>>>>>>>>>> domain, which is possible for certain diffuser flow >>>>>>>>>>>>>> conditions (and others). >>>>>>>>>>>>>> >>>>>>>>>>>>>> Paul >>>>>>>>>>>>>> ________________________________________ >>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf >>>>>>>>>>>>>> ofnek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>>>>>>> >>>>>>>>>>>>>> Hi >>>>>>>>>>>>>> >>>>>>>>>>>>>> Can some one please help me in this because I am new to nek >>>>>>>>>>>>>> >>>>>>>>>>>>>> 1) How can I create a .rea for a specific geometry say ' A >>>>>>>>>>>>>> sudden >>>>>>>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>>>>>>> >>>>>>>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> kamal >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> -- >>>>>>>>>>>>>> Josh Camp >>>>>>>>>>>>>> >>>>>>>>>>>>>> "All that is necessary for the triumph of evil is that >>>>>>>>>>>>>> good men do nothing" -- Edmund Burke >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> >>>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users _______________________________________________ Nek5000-users mailing list Nek5000-users at lists.mcs.anl.gov https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users From nek5000-users at lists.mcs.anl.gov Wed Jan 22 10:08:28 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Wed, 22 Jan 2014 18:08:28 +0200 Subject: [Nek5000-users] turboJet problem... In-Reply-To: References: , Message-ID: Hello, I am rechecking the example turboJet. I have several questions: 1. Concerning DNS/LES: in the example, the viscosity is -10935. This is certainly a very small viscosity which corresponds to LES. The parameter param(101)=1 and param(103)=0.05. If I wish to simulate DNS what would be the values of param(101),param(103) and viscosity (param(1)) in this particular example? 2. As the simulation progresses, it seems that the current CFL suddenly grows and eventually the simulation blows up. I divided up the time step up to 0.0005 and it still crashes. I am using TORDER=2 which has a larger region of stability, without a significant success. I looked at the mailing list archive and found in 2010 a posting which refers to variable time stepping: http://lists.mcs.anl.gov/pipermail/nek5000-users/2010-July/000778.html Is it relevant to my case, and if it so, how can adapt it in turboJet example? Many thanks, Barak Galanti From nek5000-users at lists.mcs.anl.gov Sun Jan 19 18:14:23 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Mon, 20 Jan 2014 01:14:23 +0100 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , Message-ID: Hi Paul , The code that you gave seem to work but the only problem is that If you could see in the code when z reaches z1 value the fraction term becomes one so smax = 2 z0 = 0 z1 = 3 scale = smax* ( z - Z0 ) / (z1 - z0 ) Scale = smax * 1 but when the z value is near to z0 the fraction value is less the inlet pipe radius scale = smax * (0.1 - Z0 ) / (z1 - z0 ) scale = 0.06 !!!! This less than the inlet radius which is 1 On Jan 20, 2014, at 12:09 AM, nek5000-users at lists.mcs.anl.gov wrote: > Hi paul, > > If I am not wrong, > I make a mesh with three straight pipes( inlet, divergent, outlet ) connected together via n2to3 so that I know the element connectivity places of the divergent section (z0,z1) and use the section what you gave > > Thank you for the code > > Kamal > > On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov wrote: > >> >> Kamal, >> >> I would do the following in usrdat2(): >> >> n=nx1*ny1*nz1*nelt >> >> do i=1,n >> x=xm1(i,1,1,1) >> y=ym1(i,1,1,1) >> z=ym1(i,1,1,1) >> scale = 1. >> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >> if (z.gt.z1) scale = smax >> xm1(i,1,1,1) = scale*x >> ym1(i,1,1,1) = scale*y >> enddo >> >> Paul >> >> Make certain that z1 and z0 correspond to z values >> that precisely coincide with element interfaces. >> >> >> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >> >>> Hi Paul, >>> >>> I looked into the Peris example but It is so what same like the stenosis example with a Cosine deformation. >>> >>> In my case it is a pipe with conical divergent. I tried to play around the variables Xm1, Ym1 and Zm1 but the mapping doesn't go well. >>> >>> Could you please help me with this. >>> >>> Thank you, >>> >>> Kamal >>> >>> >>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov wrote: >>> >>>> Hi Paul, >>>> >>>> I looked at the Helix and stenosis example but they are using cosine functions to deform >>>> >>>> I tried to use a tangent function but it bends the whole pipe. >>>> >>>> I dint look at peris example . >>>> >>>> I will take a look at it and let you know. >>>> >>>> Thank you >>>> >>>> Kamal >>>> >>>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> >>>>> Kamal, >>>>> >>>>> Have you looked at the peris example? The usr file there shows how to deform >>>>> a pipe geometry. >>>>> >>>>> Paul >>>>> >>>>> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>> To: nek5000-users at lists.mcs.anl.gov >>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>> >>>>> Dear Paul, >>>>> >>>>> I tried many ways to map my straight pipe geometry but it does not seem to work properly >>>>> >>>>> I used something like >>>>> >>>>> X = X + Z * tan ( alpha ) >>>>> Y = Y + Z* tan (alpha ) >>>>> >>>>> >>>>> even that dint work. could please help me with this >>>>> >>>>> Thank you >>>>> >>>>> Kamal. >>>>> >>>>> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>>> Hi Paul, >>>>>> >>>>>> Thanks paul. I tried working with the diverging mesh modification. >>>>>> >>>>>> I tried to use this form of equation to modify the mesh >>>>>> >>>>>> z = mx + b >>>>>> z = ny + c >>>>>> >>>>>> x = ( z - b ) / m >>>>>> y = (z - c) / n >>>>>> >>>>>> Do you think would work ? or is there any other way to input that ? >>>>>> >>>>>> Thanks, >>>>>> >>>>>> Kamal >>>>>> >>>>>> >>>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>>> Kamal, >>>>>>> >>>>>>> 1) To check for convergence, run your simulation for increasing polynomial orders ( lx1 in the SIZE file) and measure some consistent quantity (drag, TKE, etc). You can plot this quantity against lx1 and this should give you a good picture of how you are converging (without needing to change the physical mesh). >>>>>>> >>>>>>> 2) If you weren't using temperature in your simulation, you could do put the following code snippet in your userchk >>>>>>> >>>>>>> c------------------------------------------- >>>>>>> integer i, ntot >>>>>>> >>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in simulation (on THIS processor) >>>>>>> >>>>>>> do i = 1,ntot >>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + vz(i,1,1,1)**2) >>>>>>> enddo >>>>>>> >>>>>>> ifto = .true. >>>>>>> c------------------------------------------- >>>>>>> >>>>>>> I've assumed here that your density is unity. This computed kinetic energy point-wise and stores it in the temperature field. The part "ifto = .true." tells Nek to output the temperature field whenever it outputs a field file. You could then view this in visit just like you would the velocity field. >>>>>>> >>>>>>> Hope this helps! >>>>>>> >>>>>>> Josh >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, wrote: >>>>>>> Hi Paul, >>>>>>> >>>>>>> I will try that mapping, I created a straight pipe to do some simulations. >>>>>>> >>>>>>> 1) Is there a way to check my spectral convergence, so that I can do some mesh convergence study? >>>>>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>>>>> >>>>>>> Thank you, >>>>>>> Kamal >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>> Hi Kamal, >>>>>>> >>>>>>> For the geometry you describe, I would apply mesh morphing >>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>> using a subset of the mkmesh script provided in the expansion >>>>>>> example. >>>>>>> >>>>>>> If your transition region is conical, then I woud make >>>>>>> certain that the change in slope occurs at element boundaries, >>>>>>> i.e., as in the half cross-section depicted below: >>>>>>> >>>>>>> _______________ >>>>>>> /| | | >>>>>>> / | | | >>>>>>> /| | | | >>>>>>> ________________/ | | | | >>>>>>> | | | | | | | | >>>>>>> | | | | | | | | >>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>> >>>>>>> >>>>>>> Paul >>>>>>> >>>>>>> >>>>>>> >>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>> Hi Paul, >>>>>>> >>>>>>> I looked at the example and it looks very helpful, but for a sudden expansion we have only two parts (i.e) the inlet pipe and the outlet pipe. Whereas in a diverging pipe we have three section (i.e,) The inlet pipe, Diverging section and the outlet pipe. >>>>>>> >>>>>>> >>>>>>> Is it possible for me to create a 2D diverging section using mesh modification and revolve it around the centre axis to get a 3d diverging pipe ? >>>>>>> >>>>>>> >>>>>>> or should I apply the mesh modification directly to the 3d sudden expansion pipe using usrdat2() ? >>>>>>> >>>>>>> Thanks, >>>>>>> Kamal >>>>>>> >>>>>>> >>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> Hi Paul, >>>>>>> >>>>>>> Thanks a lot for the update. I will take a look at as soon as possible and keep you updated with it. >>>>>>> >>>>>>> Thank you, >>>>>>> >>>>>>> Kamal >>>>>>> >>>>>>> On Jan 14, 2014, at 9:04 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>> Kamal, >>>>>>> >>>>>>> I've added an example for a step-type expansion in a pipe. New example directory >>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>> >>>>>>> If you want a standard diffuser, I would use mesh-morphing, as outlined in the >>>>>>> nek primer, which can be found on this page: >>>>>>> >>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>> >>>>>>> I've also automated our turbulent outflow bc treatment -- one simply provides an >>>>>>> expansion factor (typically ~ 1.5) and two persistent arrays to turb_outflow(), which >>>>>>> is now in navier5.f. This can be useful when very strong vortices are leaving the >>>>>>> domain, which is possible for certain diffuser flow conditions (and others). >>>>>>> >>>>>>> Paul >>>>>>> ________________________________________ >>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf ofnek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>> >>>>>>> Hi >>>>>>> >>>>>>> Can some one please help me in this because I am new to nek >>>>>>> >>>>>>> 1) How can I create a .rea for a specific geometry say ' A sudden >>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>> >>>>>>> 2) What tool I should use to create that mesh. >>>>>>> >>>>>>> >>>>>>> Thank you >>>>>>> >>>>>>> >>>>>>> kamal >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>>> >>>>>>> >>>>>>> -- >>>>>>> Josh Camp >>>>>>> >>>>>>> "All that is necessary for the triumph of evil is that good men do nothing" -- Edmund Burke >>>>>>> >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: visit0000.png Type: image/png Size: 49924 bytes Desc: not available URL: From nek5000-users at lists.mcs.anl.gov Fri Jan 24 04:34:12 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Fri, 24 Jan 2014 11:34:12 +0100 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , , Message-ID: Hello Paul, Thanks for your reply. I am looking into the .usr file for defining the set_obj (). 1) Could you please tell me what is 'Enter the number of levels ?' in n2to3 is it the number of elements in Z direction ? 2) As you said about storing the computed vorticity in velocity field to view in VisIT, I found the routine to compute the vorticity but I am stuck about adding it to the velocity filed to VisIT ? could you please tell me how it works or any example which stores vorticity to the .fld file as a separate variable. Thank you Kamal On 22/01/2014 16:53, nek5000-users at lists.mcs.anl.gov wrote: > Axial viscous stress is given by torq_calc -- that's no problem whatsoever. You get a number as a > function of time. > > You can even get stresses on multiple subsets of the geometry (e.g., if you had multiple branches > in the domain or multiple cylinders. The drag, which is a byproduct of the torque computation (which > you can ignore), is given in terms of the viscous and pressure components separately and as the > sum of the two. > > You can identify domain boundaries by checking the boundary conditions. Here, I recommend > looking at the set_obj routines in several of the /example cases. > > > ________________________________________ > From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] > Sent: Wednesday, January 22, 2014 9:37 AM > To: nek5000-users at lists.mcs.anl.gov > Subject: Re: [Nek5000-users] Pipe with expansion > > Hello Paul > > I was thinking about taking the tangential velocity near to the wall so that I can figure out my length of the recirculation region. > > Is it possible for me to access the boundary elements of the mesh ??? so that I can take the boundary element and then obtain the velocity at that point so that I can figure out the length of my recirculation region. > > or take the *.fld file and read it to plot the datas I need. > > > I also want to calculate the axial viscous force acting on the entire pipe. > > which is given by > > C_v = F^v / ( d^2 * rho * U^2 ) = double integral ( 1/Re * (du / dr) ) dtheta dz > > > On Jan 22, 2014, at 4:07 PM, nek5000-users at lists.mcs.anl.gov wrote: > >> Hi Kamal, >> >> As I thought about it some more, if you're interested in the local wall shear stress >> magnitude I'm quite certain you can get this by plotting the magnitude of vorticity >> on the surface in question. (Note that the sign of the WSS, which in fact is a tensor >> or a vector when restricted to a given surface, is lost in this process, but that might >> not be relevant for your needs.) If that works, then you can readily compute the >> vorticity using one of the routines in nek and store the result in a velocity field, then >> view that field with VisIt. Of course WSS will require multiplication by viscosity. >> >> hth, >> >> Paul >> >> ________________________________________ >> From: nek5000-users-bounces at lists.mcs.anl.gov [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >> Sent: Tuesday, January 21, 2014 10:33 AM >> To: nek5000-users at lists.mcs.anl.gov >> Subject: Re: [Nek5000-users] Pipe with expansion >> >> Hi paul, >> >> can I make this to be drag or shear quantities to be return to the a >> separate file so that it will easy for me to plot. >> >> By the way it gives the integral quantity. Think for example I need to >> find the shear stress on the wall from the inlet to outlet at a >> particular time = 2 . How can I do that ? >> >> Is there way to find the number of elements in x,y and z direction ? >> >> On 21/01/2014 17:32, nek5000-users at lists.mcs.anl.gov wrote: >>> Hi Kamal, >>> >>> Your integrated drag quantities should be written to the logfile >>> (stdout), >>> assuming you've set the arguments in the call to be .true. >>> >>> Paul >>> >>> On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>> >>>> Hi Paul, >>>> >>>> I checked the set_obj subroutine and implemented one in my .USR file. >>>> The code seem to run without any errors but I don't find where these >>>> variables are getting stored. >>>> >>>> I use VisIT to visualize my output, even there was no change in it. >>>> >>>> do I have to define my own output file and write the variables out ? >>>> >>>> Thanks, >>>> >>>> Kamal. >>>> >>>> >>>> On 20/01/2014 21:52, nek5000-users at lists.mcs.anl.gov wrote: >>>>> Hi Kamal, >>>>> >>>>> You'll need to compute your own tke by manipulating the >>>>> velocity fields. >>>>> >>>>> You can get running averages of the requisite quantities >>>>> via calls to "avg_all" which is found in navier5.f >>>>> >>>>> You can compute shear stress on the wall simply by computing >>>>> the drag on the wall, which can be done via a call to torque_calc(), >>>>> also found in navier5.f >>>>> >>>>> If you cd to /examples and type: >>>>> >>>>> grep torq */*.usr >>>>> >>>>> you'll find many examples of calls to torque_calc. You simply >>>>> need to prescribe the surfaces on which shear is to be integrated. >>>>> >>>>> I typically write a routine "set_obj" to identify such surfaces >>>>> on the first call to usrchk. >>>>> >>>>> grep set_obj */*.usr >>>>> >>>>> will show similar examples. >>>>> >>>>> I would recommend trying this for laminar Poiseiulle flow in >>>>> a very simple channel just to check that your calls are properly >>>>> set. >>>>> >>>>> Best, >>>>> >>>>> Paul >>>>> >>>>> >>>>> On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>>> Hi Paul, >>>>>> >>>>>> Thanks and that helped. >>>>>> >>>>>> Where can I find the variables like Turbulent KE , shear stress on >>>>>> the wall. ? >>>>>> >>>>>> Do i have to activate some parameters for calculating them ? >>>>>> >>>>>> If I had to plot them. >>>>>> >>>>>> Thanks, >>>>>> Kamal >>>>>> >>>>>> >>>>>> On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>>> Kamal, >>>>>>> >>>>>>> Looks good. >>>>>>> >>>>>>> I'm guessing that one further refinement would be: >>>>>>> >>>>>>> if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) >>>>>>> if (z.gt.z1) scale = smax >>>>>>> >>>>>>> which would yield >>>>>>> >>>>>>> scale = 1 when z=z0 >>>>>>> scale = smax when z >= z1 >>>>>>> >>>>>>> Paul >>>>>>> >>>>>>> >>>>>>> >>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>>> Hi paul, >>>>>>>> >>>>>>>> The code works fine, but there should be a small change thats has >>>>>>>> to be done >>>>>>>> >>>>>>>> >>>>>>>> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >>>>>>>> if (z.gt.z1) scale = smax >>>>>>>> >>>>>>>> This creates a perfect diverging pipe. >>>>>>>> >>>>>>>> Thanks for the help paul. >>>>>>>> >>>>>>>> Kamal >>>>>>>> >>>>>>>> On Jan 20, 2014, at 12:09 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> >>>>>>>>> Hi paul, >>>>>>>>> >>>>>>>>> If I am not wrong, >>>>>>>>> I make a mesh with three straight pipes( inlet, divergent, >>>>>>>>> outlet ) connected together via n2to3 so that I know the element >>>>>>>>> connectivity places of the divergent section (z0,z1) and use the >>>>>>>>> section what you gave >>>>>>>>> >>>>>>>>> Thank you for the code >>>>>>>>> >>>>>>>>> Kamal >>>>>>>>> >>>>>>>>> On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>> >>>>>>>>>> Kamal, >>>>>>>>>> >>>>>>>>>> I would do the following in usrdat2(): >>>>>>>>>> >>>>>>>>>> n=nx1*ny1*nz1*nelt >>>>>>>>>> >>>>>>>>>> do i=1,n >>>>>>>>>> x=xm1(i,1,1,1) >>>>>>>>>> y=ym1(i,1,1,1) >>>>>>>>>> z=ym1(i,1,1,1) >>>>>>>>>> scale = 1. >>>>>>>>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>> xm1(i,1,1,1) = scale*x >>>>>>>>>> ym1(i,1,1,1) = scale*y >>>>>>>>>> enddo >>>>>>>>>> >>>>>>>>>> Paul >>>>>>>>>> >>>>>>>>>> Make certain that z1 and z0 correspond to z values >>>>>>>>>> that precisely coincide with element interfaces. >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>> >>>>>>>>>>> Hi Paul, >>>>>>>>>>> >>>>>>>>>>> I looked into the Peris example but It is so what same like >>>>>>>>>>> the stenosis example with a Cosine deformation. >>>>>>>>>>> >>>>>>>>>>> In my case it is a pipe with conical divergent. I tried to >>>>>>>>>>> play around the variables Xm1, Ym1 and Zm1 but the mapping >>>>>>>>>>> doesn't go well. >>>>>>>>>>> >>>>>>>>>>> Could you please help me with this. >>>>>>>>>>> >>>>>>>>>>> Thank you, >>>>>>>>>>> >>>>>>>>>>> Kamal >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> wrote: >>>>>>>>>>> >>>>>>>>>>>> Hi Paul, >>>>>>>>>>>> >>>>>>>>>>>> I looked at the Helix and stenosis example but they are using >>>>>>>>>>>> cosine functions to deform >>>>>>>>>>>> >>>>>>>>>>>> I tried to use a tangent function but it bends the whole pipe. >>>>>>>>>>>> >>>>>>>>>>>> I dint look at peris example . >>>>>>>>>>>> >>>>>>>>>>>> I will take a look at it and let you know. >>>>>>>>>>>> >>>>>>>>>>>> Thank you >>>>>>>>>>>> >>>>>>>>>>>> Kamal >>>>>>>>>>>> >>>>>>>>>>>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> wrote: >>>>>>>>>>>> >>>>>>>>>>>>> Kamal, >>>>>>>>>>>>> >>>>>>>>>>>>> Have you looked at the peris example? The usr file there >>>>>>>>>>>>> shows how to deform >>>>>>>>>>>>> a pipe geometry. >>>>>>>>>>>>> >>>>>>>>>>>>> Paul >>>>>>>>>>>>> >>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>>>>>>>> >>>>>>>>>>>>> Dear Paul, >>>>>>>>>>>>> >>>>>>>>>>>>> I tried many ways to map my straight pipe geometry but it >>>>>>>>>>>>> does not seem to work properly >>>>>>>>>>>>> >>>>>>>>>>>>> I used something like >>>>>>>>>>>>> >>>>>>>>>>>>> X = X + Z * tan ( alpha ) >>>>>>>>>>>>> Y = Y + Z* tan (alpha ) >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> even that dint work. could please help me with this >>>>>>>>>>>>> >>>>>>>>>>>>> Thank you >>>>>>>>>>>>> >>>>>>>>>>>>> Kamal. >>>>>>>>>>>>> >>>>>>>>>>>>> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> wrote: >>>>>>>>>>>>> >>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thanks paul. I tried working with the diverging mesh >>>>>>>>>>>>>> modification. >>>>>>>>>>>>>> >>>>>>>>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>>>>>>>> >>>>>>>>>>>>>> z = mx + b >>>>>>>>>>>>>> z = ny + c >>>>>>>>>>>>>> >>>>>>>>>>>>>> x = ( z - b ) / m >>>>>>>>>>>>>> y = (z - c) / n >>>>>>>>>>>>>> >>>>>>>>>>>>>> Do you think would work ? or is there any other way to >>>>>>>>>>>>>> input that ? >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> 1) To check for convergence, run your simulation for >>>>>>>>>>>>>>> increasing polynomial orders ( lx1 in the SIZE file) and >>>>>>>>>>>>>>> measure some consistent quantity (drag, TKE, etc). You >>>>>>>>>>>>>>> can plot this quantity against lx1 and this should give >>>>>>>>>>>>>>> you a good picture of how you are converging (without >>>>>>>>>>>>>>> needing to change the physical mesh). >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> 2) If you weren't using temperature in your simulation, >>>>>>>>>>>>>>> you could do put the following code snippet in your userchk >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>> integer i, ntot >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in >>>>>>>>>>>>>>> simulation (on THIS processor) >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> do i = 1,ntot >>>>>>>>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + >>>>>>>>>>>>>>> vz(i,1,1,1)**2) >>>>>>>>>>>>>>> enddo >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> ifto = .true. >>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I've assumed here that your density is unity. This >>>>>>>>>>>>>>> computed kinetic energy point-wise and stores it in the >>>>>>>>>>>>>>> temperature field. The part "ifto = .true." tells Nek to >>>>>>>>>>>>>>> output the temperature field whenever it outputs a field >>>>>>>>>>>>>>> file. You could then view this in visit just like you >>>>>>>>>>>>>>> would the velocity field. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Hope this helps! >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Josh >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, >>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I will try that mapping, I created a straight pipe to do >>>>>>>>>>>>>>> some simulations. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> 1) Is there a way to check my spectral convergence, so >>>>>>>>>>>>>>> that I can do some mesh convergence study? >>>>>>>>>>>>>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Hi Kamal, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> For the geometry you describe, I would apply mesh morphing >>>>>>>>>>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>>>>>>>>>> using a subset of the mkmesh script provided in the expansion >>>>>>>>>>>>>>> example. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>>>>>>>> certain that the change in slope occurs at element >>>>>>>>>>>>>>> boundaries, >>>>>>>>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> _______________ >>>>>>>>>>>>>>> /| | | >>>>>>>>>>>>>>> / | | | >>>>>>>>>>>>>>> /| | | | >>>>>>>>>>>>>>> ________________/ | | | | >>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I looked at the example and it looks very helpful, but for >>>>>>>>>>>>>>> a sudden expansion we have only two parts (i.e) the inlet >>>>>>>>>>>>>>> pipe and the outlet pipe. Whereas in a diverging pipe we >>>>>>>>>>>>>>> have three section (i.e,) The inlet pipe, Diverging >>>>>>>>>>>>>>> section and the outlet pipe. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Is it possible for me to create a 2D diverging section >>>>>>>>>>>>>>> using mesh modification and revolve it around the centre >>>>>>>>>>>>>>> axis to get a 3d diverging pipe ? >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> or should I apply the mesh modification directly to the 3d >>>>>>>>>>>>>>> sudden expansion pipe using usrdat2() ? >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Thanks a lot for the update. I will take a look at as soon >>>>>>>>>>>>>>> as possible and keep you updated with it. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> On Jan 14, 2014, at 9:04 PM, >>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I've added an example for a step-type expansion in a pipe. >>>>>>>>>>>>>>> New example directory >>>>>>>>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> If you want a standard diffuser, I would use >>>>>>>>>>>>>>> mesh-morphing, as outlined in the >>>>>>>>>>>>>>> nek primer, which can be found on this page: >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I've also automated our turbulent outflow bc treatment -- >>>>>>>>>>>>>>> one simply provides an >>>>>>>>>>>>>>> expansion factor (typically ~ 1.5) and two persistent >>>>>>>>>>>>>>> arrays to turb_outflow(), which >>>>>>>>>>>>>>> is now in navier5.f. This can be useful when very >>>>>>>>>>>>>>> strong vortices are leaving the >>>>>>>>>>>>>>> domain, which is possible for certain diffuser flow >>>>>>>>>>>>>>> conditions (and others). >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>> ________________________________________ >>>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf >>>>>>>>>>>>>>> ofnek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Hi >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Can some one please help me in this because I am new to nek >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> 1) How can I create a .rea for a specific geometry say ' A >>>>>>>>>>>>>>> sudden >>>>>>>>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> kamal >>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> -- >>>>>>>>>>>>>>> Josh Camp >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> "All that is necessary for the triumph of evil is that >>>>>>>>>>>>>>> good men do nothing" -- Edmund Burke >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users From nek5000-users at lists.mcs.anl.gov Fri Jan 24 06:02:12 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Fri, 24 Jan 2014 06:02:12 -0600 (CST) Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , , Message-ID: Kamal, 1) yes 2) standard approach to seeing vorticity would be something like the following in userchk parameter (lt=lx1*ly1*lz1*lelt) common /myjunk/ vort(lt,3),w1(lt),w2(lt) logical ifxyt integer ivout ! flag to turn geometry on/off for VisIt save ivout data ivout /0/ if (mod(istep,iostep).eq.0) then call comp_vort3(vort,w1,w2,vx,vy,vz) ifxyt = ifxyo ! put geometry into first vrt file ifxyo = .false. if (ivout.eq.0) ifxyo = .true. ivout = 1 call outpost(vort(1,1),vort(1,2),vort(1,3),pr,t,'vrt') ifxyo = ifxyt ! restore ifxyo flag to original state endif If your session name is blah, this piece of code will put vorticity into a sequence of files vrtblah0.f0000n You can instead ignore the vrt prefix and the part about the geometry with a simpler code parameter (lt=lx1*ly1*lz1*lelt) common /myjunk/ vort(lt,3),w1(lt),w2(lt) if (mod(istep,iostep).eq.0) then call comp_vort3(vort,w1,w2,vx,vy,vz) call outpost(vort(1,1),vort(1,2),vort(1,3),pr,t,'vrt') endif I usually go for this latter approach, but the choice is totally up to you. Paul On Fri, 24 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > Hello Paul, > > Thanks for your reply. I am looking into the .usr file for defining the > set_obj (). > > 1) Could you please tell me what is 'Enter the number of levels ?' in n2to3 > > is it the number of elements in Z direction ? > > 2) As you said about storing the computed vorticity in velocity field to view > in VisIT, I found the routine to compute the vorticity but I am stuck about > adding it to the velocity filed to VisIT ? could you please tell me how it > works or any example which stores vorticity to the .fld file as a separate > variable. > > > Thank you > > Kamal > > > On 22/01/2014 16:53, nek5000-users at lists.mcs.anl.gov wrote: >> Axial viscous stress is given by torq_calc -- that's no problem whatsoever. >> You get a number as a >> function of time. >> >> You can even get stresses on multiple subsets of the geometry (e.g., if you >> had multiple branches >> in the domain or multiple cylinders. The drag, which is a byproduct of >> the torque computation (which >> you can ignore), is given in terms of the viscous and pressure components >> separately and as the >> sum of the two. >> >> You can identify domain boundaries by checking the boundary conditions. >> Here, I recommend >> looking at the set_obj routines in several of the /example cases. >> >> >> ________________________________________ >> From: nek5000-users-bounces at lists.mcs.anl.gov >> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >> Sent: Wednesday, January 22, 2014 9:37 AM >> To: nek5000-users at lists.mcs.anl.gov >> Subject: Re: [Nek5000-users] Pipe with expansion >> >> Hello Paul >> >> I was thinking about taking the tangential velocity near to the wall so >> that I can figure out my length of the recirculation region. >> >> Is it possible for me to access the boundary elements of the mesh ??? so >> that I can take the boundary element and then obtain the velocity at that >> point so that I can figure out the length of my recirculation region. >> >> or take the *.fld file and read it to plot the datas I need. >> >> >> I also want to calculate the axial viscous force acting on the entire pipe. >> >> which is given by >> >> C_v = F^v / ( d^2 * rho * U^2 ) = double integral ( 1/Re * (du / dr) ) >> dtheta dz >> >> >> On Jan 22, 2014, at 4:07 PM, nek5000-users at lists.mcs.anl.gov wrote: >> >>> Hi Kamal, >>> >>> As I thought about it some more, if you're interested in the local wall >>> shear stress >>> magnitude I'm quite certain you can get this by plotting the magnitude of >>> vorticity >>> on the surface in question. (Note that the sign of the WSS, which in >>> fact is a tensor >>> or a vector when restricted to a given surface, is lost in this process, >>> but that might >>> not be relevant for your needs.) If that works, then you can readily >>> compute the >>> vorticity using one of the routines in nek and store the result in a >>> velocity field, then >>> view that field with VisIt. Of course WSS will require multiplication by >>> viscosity. >>> >>> hth, >>> >>> Paul >>> >>> ________________________________________ >>> From: nek5000-users-bounces at lists.mcs.anl.gov >>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>> Sent: Tuesday, January 21, 2014 10:33 AM >>> To: nek5000-users at lists.mcs.anl.gov >>> Subject: Re: [Nek5000-users] Pipe with expansion >>> >>> Hi paul, >>> >>> can I make this to be drag or shear quantities to be return to the a >>> separate file so that it will easy for me to plot. >>> >>> By the way it gives the integral quantity. Think for example I need to >>> find the shear stress on the wall from the inlet to outlet at a >>> particular time = 2 . How can I do that ? >>> >>> Is there way to find the number of elements in x,y and z direction ? >>> >>> On 21/01/2014 17:32, nek5000-users at lists.mcs.anl.gov wrote: >>>> Hi Kamal, >>>> >>>> Your integrated drag quantities should be written to the logfile >>>> (stdout), >>>> assuming you've set the arguments in the call to be .true. >>>> >>>> Paul >>>> >>>> On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> Hi Paul, >>>>> >>>>> I checked the set_obj subroutine and implemented one in my .USR file. >>>>> The code seem to run without any errors but I don't find where these >>>>> variables are getting stored. >>>>> >>>>> I use VisIT to visualize my output, even there was no change in it. >>>>> >>>>> do I have to define my own output file and write the variables out ? >>>>> >>>>> Thanks, >>>>> >>>>> Kamal. >>>>> >>>>> >>>>> On 20/01/2014 21:52, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> Hi Kamal, >>>>>> >>>>>> You'll need to compute your own tke by manipulating the >>>>>> velocity fields. >>>>>> >>>>>> You can get running averages of the requisite quantities >>>>>> via calls to "avg_all" which is found in navier5.f >>>>>> >>>>>> You can compute shear stress on the wall simply by computing >>>>>> the drag on the wall, which can be done via a call to torque_calc(), >>>>>> also found in navier5.f >>>>>> >>>>>> If you cd to /examples and type: >>>>>> >>>>>> grep torq */*.usr >>>>>> >>>>>> you'll find many examples of calls to torque_calc. You simply >>>>>> need to prescribe the surfaces on which shear is to be integrated. >>>>>> >>>>>> I typically write a routine "set_obj" to identify such surfaces >>>>>> on the first call to usrchk. >>>>>> >>>>>> grep set_obj */*.usr >>>>>> >>>>>> will show similar examples. >>>>>> >>>>>> I would recommend trying this for laminar Poiseiulle flow in >>>>>> a very simple channel just to check that your calls are properly >>>>>> set. >>>>>> >>>>>> Best, >>>>>> >>>>>> Paul >>>>>> >>>>>> >>>>>> On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>>> Hi Paul, >>>>>>> >>>>>>> Thanks and that helped. >>>>>>> >>>>>>> Where can I find the variables like Turbulent KE , shear stress on >>>>>>> the wall. ? >>>>>>> >>>>>>> Do i have to activate some parameters for calculating them ? >>>>>>> >>>>>>> If I had to plot them. >>>>>>> >>>>>>> Thanks, >>>>>>> Kamal >>>>>>> >>>>>>> >>>>>>> On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>>> Kamal, >>>>>>>> >>>>>>>> Looks good. >>>>>>>> >>>>>>>> I'm guessing that one further refinement would be: >>>>>>>> >>>>>>>> if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) >>>>>>>> if (z.gt.z1) scale = smax >>>>>>>> >>>>>>>> which would yield >>>>>>>> >>>>>>>> scale = 1 when z=z0 >>>>>>>> scale = smax when z >= z1 >>>>>>>> >>>>>>>> Paul >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> >>>>>>>>> Hi paul, >>>>>>>>> >>>>>>>>> The code works fine, but there should be a small change thats has >>>>>>>>> to be done >>>>>>>>> >>>>>>>>> >>>>>>>>> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>> >>>>>>>>> This creates a perfect diverging pipe. >>>>>>>>> >>>>>>>>> Thanks for the help paul. >>>>>>>>> >>>>>>>>> Kamal >>>>>>>>> >>>>>>>>> On Jan 20, 2014, at 12:09 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>> >>>>>>>>>> Hi paul, >>>>>>>>>> >>>>>>>>>> If I am not wrong, >>>>>>>>>> I make a mesh with three straight pipes( inlet, divergent, >>>>>>>>>> outlet ) connected together via n2to3 so that I know the element >>>>>>>>>> connectivity places of the divergent section (z0,z1) and use the >>>>>>>>>> section what you gave >>>>>>>>>> >>>>>>>>>> Thank you for the code >>>>>>>>>> >>>>>>>>>> Kamal >>>>>>>>>> >>>>>>>>>> On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>> >>>>>>>>>>> Kamal, >>>>>>>>>>> >>>>>>>>>>> I would do the following in usrdat2(): >>>>>>>>>>> >>>>>>>>>>> n=nx1*ny1*nz1*nelt >>>>>>>>>>> >>>>>>>>>>> do i=1,n >>>>>>>>>>> x=xm1(i,1,1,1) >>>>>>>>>>> y=ym1(i,1,1,1) >>>>>>>>>>> z=ym1(i,1,1,1) >>>>>>>>>>> scale = 1. >>>>>>>>>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>>> xm1(i,1,1,1) = scale*x >>>>>>>>>>> ym1(i,1,1,1) = scale*y >>>>>>>>>>> enddo >>>>>>>>>>> >>>>>>>>>>> Paul >>>>>>>>>>> >>>>>>>>>>> Make certain that z1 and z0 correspond to z values >>>>>>>>>>> that precisely coincide with element interfaces. >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>> >>>>>>>>>>>> Hi Paul, >>>>>>>>>>>> >>>>>>>>>>>> I looked into the Peris example but It is so what same like >>>>>>>>>>>> the stenosis example with a Cosine deformation. >>>>>>>>>>>> >>>>>>>>>>>> In my case it is a pipe with conical divergent. I tried to >>>>>>>>>>>> play around the variables Xm1, Ym1 and Zm1 but the mapping >>>>>>>>>>>> doesn't go well. >>>>>>>>>>>> >>>>>>>>>>>> Could you please help me with this. >>>>>>>>>>>> >>>>>>>>>>>> Thank you, >>>>>>>>>>>> >>>>>>>>>>>> Kamal >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> wrote: >>>>>>>>>>>> >>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>> >>>>>>>>>>>>> I looked at the Helix and stenosis example but they are using >>>>>>>>>>>>> cosine functions to deform >>>>>>>>>>>>> >>>>>>>>>>>>> I tried to use a tangent function but it bends the whole pipe. >>>>>>>>>>>>> >>>>>>>>>>>>> I dint look at peris example . >>>>>>>>>>>>> >>>>>>>>>>>>> I will take a look at it and let you know. >>>>>>>>>>>>> >>>>>>>>>>>>> Thank you >>>>>>>>>>>>> >>>>>>>>>>>>> Kamal >>>>>>>>>>>>> >>>>>>>>>>>>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> wrote: >>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>> >>>>>>>>>>>>>> Have you looked at the peris example? The usr file there >>>>>>>>>>>>>> shows how to deform >>>>>>>>>>>>>> a pipe geometry. >>>>>>>>>>>>>> >>>>>>>>>>>>>> Paul >>>>>>>>>>>>>> >>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>>>>>>>>> >>>>>>>>>>>>>> Dear Paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> I tried many ways to map my straight pipe geometry but it >>>>>>>>>>>>>> does not seem to work properly >>>>>>>>>>>>>> >>>>>>>>>>>>>> I used something like >>>>>>>>>>>>>> >>>>>>>>>>>>>> X = X + Z * tan ( alpha ) >>>>>>>>>>>>>> Y = Y + Z* tan (alpha ) >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> even that dint work. could please help me with this >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal. >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Thanks paul. I tried working with the diverging mesh >>>>>>>>>>>>>>> modification. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> z = mx + b >>>>>>>>>>>>>>> z = ny + c >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> x = ( z - b ) / m >>>>>>>>>>>>>>> y = (z - c) / n >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Do you think would work ? or is there any other way to >>>>>>>>>>>>>>> input that ? >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> 1) To check for convergence, run your simulation for >>>>>>>>>>>>>>>> increasing polynomial orders ( lx1 in the SIZE file) and >>>>>>>>>>>>>>>> measure some consistent quantity (drag, TKE, etc). You >>>>>>>>>>>>>>>> can plot this quantity against lx1 and this should give >>>>>>>>>>>>>>>> you a good picture of how you are converging (without >>>>>>>>>>>>>>>> needing to change the physical mesh). >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> 2) If you weren't using temperature in your simulation, >>>>>>>>>>>>>>>> you could do put the following code snippet in your userchk >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>>> integer i, ntot >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in >>>>>>>>>>>>>>>> simulation (on THIS processor) >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> do i = 1,ntot >>>>>>>>>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + >>>>>>>>>>>>>>>> vz(i,1,1,1)**2) >>>>>>>>>>>>>>>> enddo >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> ifto = .true. >>>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I've assumed here that your density is unity. This >>>>>>>>>>>>>>>> computed kinetic energy point-wise and stores it in the >>>>>>>>>>>>>>>> temperature field. The part "ifto = .true." tells Nek to >>>>>>>>>>>>>>>> output the temperature field whenever it outputs a field >>>>>>>>>>>>>>>> file. You could then view this in visit just like you >>>>>>>>>>>>>>>> would the velocity field. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Hope this helps! >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Josh >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, >>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I will try that mapping, I created a straight pipe to do >>>>>>>>>>>>>>>> some simulations. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> 1) Is there a way to check my spectral convergence, so >>>>>>>>>>>>>>>> that I can do some mesh convergence study? >>>>>>>>>>>>>>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Hi Kamal, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> For the geometry you describe, I would apply mesh morphing >>>>>>>>>>>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>>>>>>>>>>> using a subset of the mkmesh script provided in the expansion >>>>>>>>>>>>>>>> example. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>>>>>>>>> certain that the change in slope occurs at element >>>>>>>>>>>>>>>> boundaries, >>>>>>>>>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> _______________ >>>>>>>>>>>>>>>> /| | | >>>>>>>>>>>>>>>> / | | | >>>>>>>>>>>>>>>> /| | | | >>>>>>>>>>>>>>>> ________________/ | | | | >>>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I looked at the example and it looks very helpful, but for >>>>>>>>>>>>>>>> a sudden expansion we have only two parts (i.e) the inlet >>>>>>>>>>>>>>>> pipe and the outlet pipe. Whereas in a diverging pipe we >>>>>>>>>>>>>>>> have three section (i.e,) The inlet pipe, Diverging >>>>>>>>>>>>>>>> section and the outlet pipe. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Is it possible for me to create a 2D diverging section >>>>>>>>>>>>>>>> using mesh modification and revolve it around the centre >>>>>>>>>>>>>>>> axis to get a 3d diverging pipe ? >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> or should I apply the mesh modification directly to the 3d >>>>>>>>>>>>>>>> sudden expansion pipe using usrdat2() ? >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thanks a lot for the update. I will take a look at as soon >>>>>>>>>>>>>>>> as possible and keep you updated with it. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> On Jan 14, 2014, at 9:04 PM, >>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I've added an example for a step-type expansion in a pipe. >>>>>>>>>>>>>>>> New example directory >>>>>>>>>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> If you want a standard diffuser, I would use >>>>>>>>>>>>>>>> mesh-morphing, as outlined in the >>>>>>>>>>>>>>>> nek primer, which can be found on this page: >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I've also automated our turbulent outflow bc treatment -- >>>>>>>>>>>>>>>> one simply provides an >>>>>>>>>>>>>>>> expansion factor (typically ~ 1.5) and two persistent >>>>>>>>>>>>>>>> arrays to turb_outflow(), which >>>>>>>>>>>>>>>> is now in navier5.f. This can be useful when very >>>>>>>>>>>>>>>> strong vortices are leaving the >>>>>>>>>>>>>>>> domain, which is possible for certain diffuser flow >>>>>>>>>>>>>>>> conditions (and others). >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>> ________________________________________ >>>>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf >>>>>>>>>>>>>>>> ofnek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Hi >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Can some one please help me in this because I am new to nek >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> 1) How can I create a .rea for a specific geometry say ' A >>>>>>>>>>>>>>>> sudden >>>>>>>>>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> kamal >>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> -- >>>>>>>>>>>>>>>> Josh Camp >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> "All that is necessary for the triumph of evil is that >>>>>>>>>>>>>>>> good men do nothing" -- Edmund Burke >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > On Fri, 24 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > Hello Paul, > > Thanks for your reply. I am looking into the .usr file for defining the > set_obj (). > > 1) Could you please tell me what is 'Enter the number of levels ?' in n2to3 > > is it the number of elements in Z direction ? > > 2) As you said about storing the computed vorticity in velocity field to view > in VisIT, I found the routine to compute the vorticity but I am stuck about > adding it to the velocity filed to VisIT ? could you please tell me how it > works or any example which stores vorticity to the .fld file as a separate > variable. > > > Thank you > > Kamal > > > On 22/01/2014 16:53, nek5000-users at lists.mcs.anl.gov wrote: >> Axial viscous stress is given by torq_calc -- that's no problem whatsoever. >> You get a number as a >> function of time. >> >> You can even get stresses on multiple subsets of the geometry (e.g., if you >> had multiple branches >> in the domain or multiple cylinders. The drag, which is a byproduct of >> the torque computation (which >> you can ignore), is given in terms of the viscous and pressure components >> separately and as the >> sum of the two. >> >> You can identify domain boundaries by checking the boundary conditions. >> Here, I recommend >> looking at the set_obj routines in several of the /example cases. >> >> >> ________________________________________ >> From: nek5000-users-bounces at lists.mcs.anl.gov >> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >> Sent: Wednesday, January 22, 2014 9:37 AM >> To: nek5000-users at lists.mcs.anl.gov >> Subject: Re: [Nek5000-users] Pipe with expansion >> >> Hello Paul >> >> I was thinking about taking the tangential velocity near to the wall so >> that I can figure out my length of the recirculation region. >> >> Is it possible for me to access the boundary elements of the mesh ??? so >> that I can take the boundary element and then obtain the velocity at that >> point so that I can figure out the length of my recirculation region. >> >> or take the *.fld file and read it to plot the datas I need. >> >> >> I also want to calculate the axial viscous force acting on the entire pipe. >> >> which is given by >> >> C_v = F^v / ( d^2 * rho * U^2 ) = double integral ( 1/Re * (du / dr) ) >> dtheta dz >> >> >> On Jan 22, 2014, at 4:07 PM, nek5000-users at lists.mcs.anl.gov wrote: >> >>> Hi Kamal, >>> >>> As I thought about it some more, if you're interested in the local wall >>> shear stress >>> magnitude I'm quite certain you can get this by plotting the magnitude of >>> vorticity >>> on the surface in question. (Note that the sign of the WSS, which in >>> fact is a tensor >>> or a vector when restricted to a given surface, is lost in this process, >>> but that might >>> not be relevant for your needs.) If that works, then you can readily >>> compute the >>> vorticity using one of the routines in nek and store the result in a >>> velocity field, then >>> view that field with VisIt. Of course WSS will require multiplication by >>> viscosity. >>> >>> hth, >>> >>> Paul >>> >>> ________________________________________ >>> From: nek5000-users-bounces at lists.mcs.anl.gov >>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>> Sent: Tuesday, January 21, 2014 10:33 AM >>> To: nek5000-users at lists.mcs.anl.gov >>> Subject: Re: [Nek5000-users] Pipe with expansion >>> >>> Hi paul, >>> >>> can I make this to be drag or shear quantities to be return to the a >>> separate file so that it will easy for me to plot. >>> >>> By the way it gives the integral quantity. Think for example I need to >>> find the shear stress on the wall from the inlet to outlet at a >>> particular time = 2 . How can I do that ? >>> >>> Is there way to find the number of elements in x,y and z direction ? >>> >>> On 21/01/2014 17:32, nek5000-users at lists.mcs.anl.gov wrote: >>>> Hi Kamal, >>>> >>>> Your integrated drag quantities should be written to the logfile >>>> (stdout), >>>> assuming you've set the arguments in the call to be .true. >>>> >>>> Paul >>>> >>>> On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> Hi Paul, >>>>> >>>>> I checked the set_obj subroutine and implemented one in my .USR file. >>>>> The code seem to run without any errors but I don't find where these >>>>> variables are getting stored. >>>>> >>>>> I use VisIT to visualize my output, even there was no change in it. >>>>> >>>>> do I have to define my own output file and write the variables out ? >>>>> >>>>> Thanks, >>>>> >>>>> Kamal. >>>>> >>>>> >>>>> On 20/01/2014 21:52, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> Hi Kamal, >>>>>> >>>>>> You'll need to compute your own tke by manipulating the >>>>>> velocity fields. >>>>>> >>>>>> You can get running averages of the requisite quantities >>>>>> via calls to "avg_all" which is found in navier5.f >>>>>> >>>>>> You can compute shear stress on the wall simply by computing >>>>>> the drag on the wall, which can be done via a call to torque_calc(), >>>>>> also found in navier5.f >>>>>> >>>>>> If you cd to /examples and type: >>>>>> >>>>>> grep torq */*.usr >>>>>> >>>>>> you'll find many examples of calls to torque_calc. You simply >>>>>> need to prescribe the surfaces on which shear is to be integrated. >>>>>> >>>>>> I typically write a routine "set_obj" to identify such surfaces >>>>>> on the first call to usrchk. >>>>>> >>>>>> grep set_obj */*.usr >>>>>> >>>>>> will show similar examples. >>>>>> >>>>>> I would recommend trying this for laminar Poiseiulle flow in >>>>>> a very simple channel just to check that your calls are properly >>>>>> set. >>>>>> >>>>>> Best, >>>>>> >>>>>> Paul >>>>>> >>>>>> >>>>>> On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>>> Hi Paul, >>>>>>> >>>>>>> Thanks and that helped. >>>>>>> >>>>>>> Where can I find the variables like Turbulent KE , shear stress on >>>>>>> the wall. ? >>>>>>> >>>>>>> Do i have to activate some parameters for calculating them ? >>>>>>> >>>>>>> If I had to plot them. >>>>>>> >>>>>>> Thanks, >>>>>>> Kamal >>>>>>> >>>>>>> >>>>>>> On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>>> Kamal, >>>>>>>> >>>>>>>> Looks good. >>>>>>>> >>>>>>>> I'm guessing that one further refinement would be: >>>>>>>> >>>>>>>> if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) >>>>>>>> if (z.gt.z1) scale = smax >>>>>>>> >>>>>>>> which would yield >>>>>>>> >>>>>>>> scale = 1 when z=z0 >>>>>>>> scale = smax when z >= z1 >>>>>>>> >>>>>>>> Paul >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> >>>>>>>>> Hi paul, >>>>>>>>> >>>>>>>>> The code works fine, but there should be a small change thats has >>>>>>>>> to be done >>>>>>>>> >>>>>>>>> >>>>>>>>> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>> >>>>>>>>> This creates a perfect diverging pipe. >>>>>>>>> >>>>>>>>> Thanks for the help paul. >>>>>>>>> >>>>>>>>> Kamal >>>>>>>>> >>>>>>>>> On Jan 20, 2014, at 12:09 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>> >>>>>>>>>> Hi paul, >>>>>>>>>> >>>>>>>>>> If I am not wrong, >>>>>>>>>> I make a mesh with three straight pipes( inlet, divergent, >>>>>>>>>> outlet ) connected together via n2to3 so that I know the element >>>>>>>>>> connectivity places of the divergent section (z0,z1) and use the >>>>>>>>>> section what you gave >>>>>>>>>> >>>>>>>>>> Thank you for the code >>>>>>>>>> >>>>>>>>>> Kamal >>>>>>>>>> >>>>>>>>>> On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>> >>>>>>>>>>> Kamal, >>>>>>>>>>> >>>>>>>>>>> I would do the following in usrdat2(): >>>>>>>>>>> >>>>>>>>>>> n=nx1*ny1*nz1*nelt >>>>>>>>>>> >>>>>>>>>>> do i=1,n >>>>>>>>>>> x=xm1(i,1,1,1) >>>>>>>>>>> y=ym1(i,1,1,1) >>>>>>>>>>> z=ym1(i,1,1,1) >>>>>>>>>>> scale = 1. >>>>>>>>>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>>> xm1(i,1,1,1) = scale*x >>>>>>>>>>> ym1(i,1,1,1) = scale*y >>>>>>>>>>> enddo >>>>>>>>>>> >>>>>>>>>>> Paul >>>>>>>>>>> >>>>>>>>>>> Make certain that z1 and z0 correspond to z values >>>>>>>>>>> that precisely coincide with element interfaces. >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>> >>>>>>>>>>>> Hi Paul, >>>>>>>>>>>> >>>>>>>>>>>> I looked into the Peris example but It is so what same like >>>>>>>>>>>> the stenosis example with a Cosine deformation. >>>>>>>>>>>> >>>>>>>>>>>> In my case it is a pipe with conical divergent. I tried to >>>>>>>>>>>> play around the variables Xm1, Ym1 and Zm1 but the mapping >>>>>>>>>>>> doesn't go well. >>>>>>>>>>>> >>>>>>>>>>>> Could you please help me with this. >>>>>>>>>>>> >>>>>>>>>>>> Thank you, >>>>>>>>>>>> >>>>>>>>>>>> Kamal >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> wrote: >>>>>>>>>>>> >>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>> >>>>>>>>>>>>> I looked at the Helix and stenosis example but they are using >>>>>>>>>>>>> cosine functions to deform >>>>>>>>>>>>> >>>>>>>>>>>>> I tried to use a tangent function but it bends the whole pipe. >>>>>>>>>>>>> >>>>>>>>>>>>> I dint look at peris example . >>>>>>>>>>>>> >>>>>>>>>>>>> I will take a look at it and let you know. >>>>>>>>>>>>> >>>>>>>>>>>>> Thank you >>>>>>>>>>>>> >>>>>>>>>>>>> Kamal >>>>>>>>>>>>> >>>>>>>>>>>>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> wrote: >>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>> >>>>>>>>>>>>>> Have you looked at the peris example? The usr file there >>>>>>>>>>>>>> shows how to deform >>>>>>>>>>>>>> a pipe geometry. >>>>>>>>>>>>>> >>>>>>>>>>>>>> Paul >>>>>>>>>>>>>> >>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>>>>>>>>> >>>>>>>>>>>>>> Dear Paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> I tried many ways to map my straight pipe geometry but it >>>>>>>>>>>>>> does not seem to work properly >>>>>>>>>>>>>> >>>>>>>>>>>>>> I used something like >>>>>>>>>>>>>> >>>>>>>>>>>>>> X = X + Z * tan ( alpha ) >>>>>>>>>>>>>> Y = Y + Z* tan (alpha ) >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> even that dint work. could please help me with this >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal. >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Thanks paul. I tried working with the diverging mesh >>>>>>>>>>>>>>> modification. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> z = mx + b >>>>>>>>>>>>>>> z = ny + c >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> x = ( z - b ) / m >>>>>>>>>>>>>>> y = (z - c) / n >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Do you think would work ? or is there any other way to >>>>>>>>>>>>>>> input that ? >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> 1) To check for convergence, run your simulation for >>>>>>>>>>>>>>>> increasing polynomial orders ( lx1 in the SIZE file) and >>>>>>>>>>>>>>>> measure some consistent quantity (drag, TKE, etc). You >>>>>>>>>>>>>>>> can plot this quantity against lx1 and this should give >>>>>>>>>>>>>>>> you a good picture of how you are converging (without >>>>>>>>>>>>>>>> needing to change the physical mesh). >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> 2) If you weren't using temperature in your simulation, >>>>>>>>>>>>>>>> you could do put the following code snippet in your userchk >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>>> integer i, ntot >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in >>>>>>>>>>>>>>>> simulation (on THIS processor) >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> do i = 1,ntot >>>>>>>>>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + >>>>>>>>>>>>>>>> vz(i,1,1,1)**2) >>>>>>>>>>>>>>>> enddo >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> ifto = .true. >>>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I've assumed here that your density is unity. This >>>>>>>>>>>>>>>> computed kinetic energy point-wise and stores it in the >>>>>>>>>>>>>>>> temperature field. The part "ifto = .true." tells Nek to >>>>>>>>>>>>>>>> output the temperature field whenever it outputs a field >>>>>>>>>>>>>>>> file. You could then view this in visit just like you >>>>>>>>>>>>>>>> would the velocity field. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Hope this helps! >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Josh >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, >>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I will try that mapping, I created a straight pipe to do >>>>>>>>>>>>>>>> some simulations. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> 1) Is there a way to check my spectral convergence, so >>>>>>>>>>>>>>>> that I can do some mesh convergence study? >>>>>>>>>>>>>>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Hi Kamal, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> For the geometry you describe, I would apply mesh morphing >>>>>>>>>>>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>>>>>>>>>>> using a subset of the mkmesh script provided in the expansion >>>>>>>>>>>>>>>> example. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>>>>>>>>> certain that the change in slope occurs at element >>>>>>>>>>>>>>>> boundaries, >>>>>>>>>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> _______________ >>>>>>>>>>>>>>>> /| | | >>>>>>>>>>>>>>>> / | | | >>>>>>>>>>>>>>>> /| | | | >>>>>>>>>>>>>>>> ________________/ | | | | >>>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I looked at the example and it looks very helpful, but for >>>>>>>>>>>>>>>> a sudden expansion we have only two parts (i.e) the inlet >>>>>>>>>>>>>>>> pipe and the outlet pipe. Whereas in a diverging pipe we >>>>>>>>>>>>>>>> have three section (i.e,) The inlet pipe, Diverging >>>>>>>>>>>>>>>> section and the outlet pipe. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Is it possible for me to create a 2D diverging section >>>>>>>>>>>>>>>> using mesh modification and revolve it around the centre >>>>>>>>>>>>>>>> axis to get a 3d diverging pipe ? >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> or should I apply the mesh modification directly to the 3d >>>>>>>>>>>>>>>> sudden expansion pipe using usrdat2() ? >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thanks a lot for the update. I will take a look at as soon >>>>>>>>>>>>>>>> as possible and keep you updated with it. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> On Jan 14, 2014, at 9:04 PM, >>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I've added an example for a step-type expansion in a pipe. >>>>>>>>>>>>>>>> New example directory >>>>>>>>>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> If you want a standard diffuser, I would use >>>>>>>>>>>>>>>> mesh-morphing, as outlined in the >>>>>>>>>>>>>>>> nek primer, which can be found on this page: >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I've also automated our turbulent outflow bc treatment -- >>>>>>>>>>>>>>>> one simply provides an >>>>>>>>>>>>>>>> expansion factor (typically ~ 1.5) and two persistent >>>>>>>>>>>>>>>> arrays to turb_outflow(), which >>>>>>>>>>>>>>>> is now in navier5.f. This can be useful when very >>>>>>>>>>>>>>>> strong vortices are leaving the >>>>>>>>>>>>>>>> domain, which is possible for certain diffuser flow >>>>>>>>>>>>>>>> conditions (and others). >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>> ________________________________________ >>>>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf >>>>>>>>>>>>>>>> ofnek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Hi >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Can some one please help me in this because I am new to nek >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> 1) How can I create a .rea for a specific geometry say ' A >>>>>>>>>>>>>>>> sudden >>>>>>>>>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> kamal >>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> -- >>>>>>>>>>>>>>>> Josh Camp >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> "All that is necessary for the triumph of evil is that >>>>>>>>>>>>>>>> good men do nothing" -- Edmund Burke >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > From nek5000-users at lists.mcs.anl.gov Tue Jan 28 03:39:11 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 28 Jan 2014 10:39:11 +0100 Subject: [Nek5000-users] Post processing bypass Message-ID: Hi All, Any follow up please? Regards, JP On 17 January 2014 11:05, Jean-Paul Mollicone wrote: > Dear All, > > A quick question; is there a way to run nek5000 in post-processing mode > (i.e. with nsteps=0) BUT without re-generating the mesh? > > The use would be for example to carry out post-processing from large-scale > simulation data from a high-performance computer on a less powerful > computer (that is not able to re-generate the mesh without sufficient RAM, > etc) > > Thank you, > JP > -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Tue Jan 28 03:58:06 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 28 Jan 2014 10:58:06 +0100 Subject: [Nek5000-users] mpi issue Message-ID: Hello, I run into this error with mpi. I am not sure what is about. Has someone an idea? Thank you! Best Tubois ############################################################# # Compilation successful! # ############################################################# text data bss dec hex filename 2405375 3336 196307656 198716367 bd82bcf nek5000 mv: cannot stat `ext_cyl.log.': No such file or directory mv: cannot stat `ext_cyl.sch': No such file or directory -------------------------------------------------------------------------- mpiexec was unable to launch the specified application as it could not find an executable: Executable: -4 Node: boquette while attempting to start process rank 0. -------------------------------------------------------------------------- -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Tue Jan 28 08:48:50 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 28 Jan 2014 08:48:50 -0600 (CST) Subject: [Nek5000-users] Post processing bypass In-Reply-To: References: Message-ID: Hi JP, I'm not certain what you mean about regenerating the mesh. In any case, one space-saving measure for postprocessing is to set lgmres=1 and lxprev=1 in SIZE. You can also try lorder=1, lx2=lx1-2 (same for ly2,lz2), and ldimt1=1. Hopefully this will help. Best, Paul On Tue, 28 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > Hi All, > > Any follow up please? > > Regards, > JP > > > On 17 January 2014 11:05, Jean-Paul Mollicone wrote: > >> Dear All, >> >> A quick question; is there a way to run nek5000 in post-processing mode >> (i.e. with nsteps=0) BUT without re-generating the mesh? >> >> The use would be for example to carry out post-processing from large-scale >> simulation data from a high-performance computer on a less powerful >> computer (that is not able to re-generate the mesh without sufficient RAM, >> etc) >> >> Thank you, >> JP >> > From nek5000-users at lists.mcs.anl.gov Tue Jan 28 10:05:39 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 28 Jan 2014 11:05:39 -0500 Subject: [Nek5000-users] NEK5000 User Group Metting Message-ID: Hi All, Is there any more info on the possibility of a User Group Meeting this year? Thanks, Murph -- /Confidentiality Notice: I swear and affirm that I will not retransmit, discuss, or disseminate any information in this message to anyone other than the intended recipients.However, at this very second, every entity in the known universe is reading this message.This includes the US Government, Foreign Governments, all telecommunications carriers, all Internet service companies, anyone buying adds from said service companies, most major hardware and software vendors, all hackers and kiddie-scripters older than about 6, and any space aliens within subspace communications range of Earth.Tin Foil Helmets do not work./ ** *Murphy Leo O'Dea, PE"Murph"* PhD Student, Mechanical Engineering /School Of Engineering And Computer Science/ /Oakland University/ mlodea at oakland.edu http://www.secs.oakland.edu/~mlodea/ -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: image002.jpg Type: image/jpeg Size: 4893 bytes Desc: not available URL: From nek5000-users at lists.mcs.anl.gov Tue Jan 28 11:35:30 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 28 Jan 2014 18:35:30 +0100 Subject: [Nek5000-users] Post processing bypass Message-ID: Dear Paul, Thank you. I was basically looking for the space-saving measures you mentioned. Best regards, JP On 28 January 2014 10:39, Jean-Paul Mollicone wrote: > Hi All, > > Any follow up please? > > Regards, > JP > > > On 17 January 2014 11:05, Jean-Paul Mollicone wrote: > >> Dear All, >> >> A quick question; is there a way to run nek5000 in post-processing mode >> (i.e. with nsteps=0) BUT without re-generating the mesh? >> >> The use would be for example to carry out post-processing from >> large-scale simulation data from a high-performance computer on a less >> powerful computer (that is not able to re-generate the mesh without >> sufficient RAM, etc) >> >> Thank you, >> JP >> > > -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Tue Jan 28 12:42:19 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 28 Jan 2014 12:42:19 -0600 Subject: [Nek5000-users] mpi issue In-Reply-To: References: Message-ID: Hi Tubois, What command are you using to submit the run? Katie On Tue, Jan 28, 2014 at 3:58 AM, wrote: > Hello, > > I run into this error with mpi. I am not sure what is about. Has someone > an idea? Thank you! > > Best > > Tubois > > ############################################################# > # Compilation successful! # > ############################################################# > text data bss dec hex filename > 2405375 3336 196307656 198716367 bd82bcf nek5000 > > > mv: cannot stat `ext_cyl.log.': No such file or directory > mv: cannot stat `ext_cyl.sch': No such file or directory > -------------------------------------------------------------------------- > mpiexec was unable to launch the specified application as it could not > find an executable: > > Executable: -4 > Node: boquette > > while attempting to start process rank 0. > -------------------------------------------------------------------------- > > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Tue Jan 28 15:45:29 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Tue, 28 Jan 2014 23:45:29 +0200 Subject: [Nek5000-users] turboJet problem... In-Reply-To: References: , Message-ID: Hello, I am rechecking the example turboJet. I have several questions: 1. Concerning DNS/LES: in the example, the viscosity is -10935. This is certainly a very small viscosity which corresponds to LES. The parameter param(101)=1 and param(103)=0.05. If I wish to simulate DNS what would be the values of param(101),param(103) and viscosity (param(1)) in this particular example? 2. As the simulation progresses, it seems that the current CFL suddenly grows and eventually the simulation blows up. I divided up the time step up to 0.0005 and it still crashes. I am using TORDER=2 which has a larger region of stability, without a significant success. I looked at the mailing list archive and found in 2010 a posting which refers to variable time stepping: http://lists.mcs.anl.gov/pipermail/nek5000-users/2010-July/000778.html Is it relevant to my case, and if it so, how can adapt it in turboJet example? Many thanks, Barak Galanti _______________________________________________ Nek5000-users mailing list Nek5000-users at lists.mcs.anl.gov https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users From nek5000-users at lists.mcs.anl.gov Wed Jan 29 02:11:22 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Wed, 29 Jan 2014 09:11:22 +0100 Subject: [Nek5000-users] mpi issue In-Reply-To: References: Message-ID: Hi, Katie I changed mpiexec -np $2 ./nek5000 to mpiexec -4 $2 ./nek5000 in ~/bin/nekmpi to set 4 proc as defaut then type nekmpi ext_cyl Then I got the error Tubois On Tue, Jan 28, 2014 at 7:42 PM, wrote: > Hi Tubois, > > What command are you using to submit the run? > > Katie > > > On Tue, Jan 28, 2014 at 3:58 AM, wrote: > >> Hello, >> >> I run into this error with mpi. I am not sure what is about. Has someone >> an idea? Thank you! >> >> Best >> >> Tubois >> >> ############################################################# >> # Compilation successful! # >> ############################################################# >> text data bss dec hex filename >> 2405375 3336 196307656 198716367 bd82bcf nek5000 >> >> >> mv: cannot stat `ext_cyl.log.': No such file or directory >> mv: cannot stat `ext_cyl.sch': No such file or directory >> -------------------------------------------------------------------------- >> mpiexec was unable to launch the specified application as it could not >> find an executable: >> >> Executable: -4 >> Node: boquette >> >> while attempting to start process rank 0. >> -------------------------------------------------------------------------- >> >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Wed Jan 29 02:13:56 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Wed, 29 Jan 2014 09:13:56 +0100 Subject: [Nek5000-users] mpi issue In-Reply-To: References: Message-ID: Hi Tubois. I guess you need to let the -np. The command line actually is: mpiexec -np 4 ./nek5000 Le 29 janv. 2014 09:11, a ?crit : > Hi, Katie > > I changed mpiexec -np $2 ./nek5000 > to mpiexec -4 $2 ./nek5000 in ~/bin/nekmpi to set 4 proc as defaut > then type nekmpi ext_cyl > > Then I got the error > > Tubois > > > > > On Tue, Jan 28, 2014 at 7:42 PM, wrote: > >> Hi Tubois, >> >> What command are you using to submit the run? >> >> Katie >> >> >> On Tue, Jan 28, 2014 at 3:58 AM, wrote: >> >>> Hello, >>> >>> I run into this error with mpi. I am not sure what is about. Has someone >>> an idea? Thank you! >>> >>> Best >>> >>> Tubois >>> >>> ############################################################# >>> # Compilation successful! # >>> ############################################################# >>> text data bss dec hex filename >>> 2405375 3336 196307656 198716367 bd82bcf nek5000 >>> >>> >>> mv: cannot stat `ext_cyl.log.': No such file or directory >>> mv: cannot stat `ext_cyl.sch': No such file or directory >>> >>> -------------------------------------------------------------------------- >>> mpiexec was unable to launch the specified application as it could not >>> find an executable: >>> >>> Executable: -4 >>> Node: boquette >>> >>> while attempting to start process rank 0. >>> >>> -------------------------------------------------------------------------- >>> >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Wed Jan 29 02:25:32 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Wed, 29 Jan 2014 09:25:32 +0100 Subject: [Nek5000-users] mpi issue In-Reply-To: References: Message-ID: Hi, Katie, Thank you very much. It works. Best Tubois On Wed, Jan 29, 2014 at 9:13 AM, wrote: > Hi Tubois. > > I guess you need to let the -np. The command line actually is: mpiexec -np > 4 ./nek5000 > Le 29 janv. 2014 09:11, a ?crit : > > Hi, Katie >> >> I changed mpiexec -np $2 ./nek5000 >> to mpiexec -4 $2 ./nek5000 in ~/bin/nekmpi to set 4 proc as defaut >> then type nekmpi ext_cyl >> >> Then I got the error >> >> Tubois >> >> >> >> >> On Tue, Jan 28, 2014 at 7:42 PM, wrote: >> >>> Hi Tubois, >>> >>> What command are you using to submit the run? >>> >>> Katie >>> >>> >>> On Tue, Jan 28, 2014 at 3:58 AM, wrote: >>> >>>> Hello, >>>> >>>> I run into this error with mpi. I am not sure what is about. Has >>>> someone an idea? Thank you! >>>> >>>> Best >>>> >>>> Tubois >>>> >>>> ############################################################# >>>> # Compilation successful! # >>>> ############################################################# >>>> text data bss dec hex filename >>>> 2405375 3336 196307656 198716367 bd82bcf nek5000 >>>> >>>> >>>> mv: cannot stat `ext_cyl.log.': No such file or directory >>>> mv: cannot stat `ext_cyl.sch': No such file or directory >>>> >>>> -------------------------------------------------------------------------- >>>> mpiexec was unable to launch the specified application as it could not >>>> find an executable: >>>> >>>> Executable: -4 >>>> Node: boquette >>>> >>>> while attempting to start process rank 0. >>>> >>>> -------------------------------------------------------------------------- >>>> >>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>>> >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Wed Jan 29 09:01:37 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Wed, 29 Jan 2014 16:01:37 +0100 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , , Message-ID: Hello Paul, Thanks for the vorticity output and it worked. 1) I created a set-obj() for my pipe but how can I be sure that it has taken the full pipe wall surface in to account ? I have attached the divpipe.usr file for your reference could you please take a look at it. 2) I even took torque_calc in to the .usr file and it gives out something like this 200 1.00000000000E+00 -9.76942759878E-06 -8.98721249598E-06 -7.82215102801E-07 1torqx 200 1.00000000000E+00 -6.69169235606E-06 -6.35251009840E-06 -3.39182257669E-07 1torqy 200 1.00000000000E+00 9.50518561890E-10 1.50349344990E-13 9.50368212545E-10 1torqz if I am not wrong are these the value of surface integral of viscous force in three components of velocity along three directions taken in the set_obj() ? because I would like to calculate this C_v = F^v / ( d^2 * rho * U^2 ) = double integral ( 1/Re * (du / dr) ) dtheta dz Thank you, Kamal. On 24/01/2014 13:02, nek5000-users at lists.mcs.anl.gov wrote: > > > > Kamal, > > 1) yes > > 2) standard approach to seeing vorticity would be something > like the following in userchk > > parameter (lt=lx1*ly1*lz1*lelt) > common /myjunk/ vort(lt,3),w1(lt),w2(lt) > logical ifxyt > integer ivout ! flag to turn geometry on/off for VisIt > save ivout > data ivout /0/ > > > if (mod(istep,iostep).eq.0) then > call comp_vort3(vort,w1,w2,vx,vy,vz) > > ifxyt = ifxyo ! put geometry into first vrt file > ifxyo = .false. > if (ivout.eq.0) ifxyo = .true. > ivout = 1 > > call outpost(vort(1,1),vort(1,2),vort(1,3),pr,t,'vrt') > > ifxyo = ifxyt ! restore ifxyo flag to original state > > endif > > > If your session name is blah, this piece of code will put > vorticity into a sequence of files vrtblah0.f0000n > > You can instead ignore the vrt prefix and the part about the > geometry with a simpler code > > parameter (lt=lx1*ly1*lz1*lelt) > common /myjunk/ vort(lt,3),w1(lt),w2(lt) > > if (mod(istep,iostep).eq.0) then > call comp_vort3(vort,w1,w2,vx,vy,vz) > call outpost(vort(1,1),vort(1,2),vort(1,3),pr,t,'vrt') > endif > > I usually go for this latter approach, but the choice is > totally up to you. > > Paul > > > > > > On Fri, 24 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > >> Hello Paul, >> >> Thanks for your reply. I am looking into the .usr file for defining >> the set_obj (). >> >> 1) Could you please tell me what is 'Enter the number of levels ?' in >> n2to3 >> >> is it the number of elements in Z direction ? >> >> 2) As you said about storing the computed vorticity in velocity field >> to view in VisIT, I found the routine to compute the vorticity but I >> am stuck about adding it to the velocity filed to VisIT ? could you >> please tell me how it works or any example which stores vorticity to >> the .fld file as a separate variable. >> >> >> Thank you >> >> Kamal >> >> >> On 22/01/2014 16:53, nek5000-users at lists.mcs.anl.gov wrote: >>> Axial viscous stress is given by torq_calc -- that's no problem >>> whatsoever. You get a number as a >>> function of time. >>> >>> You can even get stresses on multiple subsets of the geometry (e.g., >>> if you had multiple branches >>> in the domain or multiple cylinders. The drag, which is a >>> byproduct of the torque computation (which >>> you can ignore), is given in terms of the viscous and pressure >>> components separately and as the >>> sum of the two. >>> >>> You can identify domain boundaries by checking the boundary >>> conditions. Here, I recommend >>> looking at the set_obj routines in several of the /example cases. >>> >>> >>> ________________________________________ >>> From: nek5000-users-bounces at lists.mcs.anl.gov >>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>> Sent: Wednesday, January 22, 2014 9:37 AM >>> To: nek5000-users at lists.mcs.anl.gov >>> Subject: Re: [Nek5000-users] Pipe with expansion >>> >>> Hello Paul >>> >>> I was thinking about taking the tangential velocity near to the wall >>> so that I can figure out my length of the recirculation region. >>> >>> Is it possible for me to access the boundary elements of the mesh >>> ??? so that I can take the boundary element and then obtain the >>> velocity at that point so that I can figure out the length of my >>> recirculation region. >>> >>> or take the *.fld file and read it to plot the datas I need. >>> >>> >>> I also want to calculate the axial viscous force acting on the >>> entire pipe. >>> >>> which is given by >>> >>> C_v = F^v / ( d^2 * rho * U^2 ) = double integral ( 1/Re * (du / >>> dr) ) dtheta dz >>> >>> >>> On Jan 22, 2014, at 4:07 PM, nek5000-users at lists.mcs.anl.gov wrote: >>> >>>> Hi Kamal, >>>> >>>> As I thought about it some more, if you're interested in the local >>>> wall shear stress >>>> magnitude I'm quite certain you can get this by plotting the >>>> magnitude of vorticity >>>> on the surface in question. (Note that the sign of the WSS, which >>>> in fact is a tensor >>>> or a vector when restricted to a given surface, is lost in this >>>> process, but that might >>>> not be relevant for your needs.) If that works, then you can >>>> readily compute the >>>> vorticity using one of the routines in nek and store the result in >>>> a velocity field, then >>>> view that field with VisIt. Of course WSS will require >>>> multiplication by viscosity. >>>> >>>> hth, >>>> >>>> Paul >>>> >>>> ________________________________________ >>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>> Sent: Tuesday, January 21, 2014 10:33 AM >>>> To: nek5000-users at lists.mcs.anl.gov >>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>> >>>> Hi paul, >>>> >>>> can I make this to be drag or shear quantities to be return to the a >>>> separate file so that it will easy for me to plot. >>>> >>>> By the way it gives the integral quantity. Think for example I need to >>>> find the shear stress on the wall from the inlet to outlet at a >>>> particular time = 2 . How can I do that ? >>>> >>>> Is there way to find the number of elements in x,y and z direction ? >>>> >>>> On 21/01/2014 17:32, nek5000-users at lists.mcs.anl.gov wrote: >>>>> Hi Kamal, >>>>> >>>>> Your integrated drag quantities should be written to the logfile >>>>> (stdout), >>>>> assuming you've set the arguments in the call to be .true. >>>>> >>>>> Paul >>>>> >>>>> On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>>> Hi Paul, >>>>>> >>>>>> I checked the set_obj subroutine and implemented one in my .USR >>>>>> file. >>>>>> The code seem to run without any errors but I don't find where these >>>>>> variables are getting stored. >>>>>> >>>>>> I use VisIT to visualize my output, even there was no change in it. >>>>>> >>>>>> do I have to define my own output file and write the variables out ? >>>>>> >>>>>> Thanks, >>>>>> >>>>>> Kamal. >>>>>> >>>>>> >>>>>> On 20/01/2014 21:52, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> Hi Kamal, >>>>>>> >>>>>>> You'll need to compute your own tke by manipulating the >>>>>>> velocity fields. >>>>>>> >>>>>>> You can get running averages of the requisite quantities >>>>>>> via calls to "avg_all" which is found in navier5.f >>>>>>> >>>>>>> You can compute shear stress on the wall simply by computing >>>>>>> the drag on the wall, which can be done via a call to >>>>>>> torque_calc(), >>>>>>> also found in navier5.f >>>>>>> >>>>>>> If you cd to /examples and type: >>>>>>> >>>>>>> grep torq */*.usr >>>>>>> >>>>>>> you'll find many examples of calls to torque_calc. You simply >>>>>>> need to prescribe the surfaces on which shear is to be integrated. >>>>>>> >>>>>>> I typically write a routine "set_obj" to identify such surfaces >>>>>>> on the first call to usrchk. >>>>>>> >>>>>>> grep set_obj */*.usr >>>>>>> >>>>>>> will show similar examples. >>>>>>> >>>>>>> I would recommend trying this for laminar Poiseiulle flow in >>>>>>> a very simple channel just to check that your calls are properly >>>>>>> set. >>>>>>> >>>>>>> Best, >>>>>>> >>>>>>> Paul >>>>>>> >>>>>>> >>>>>>> On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>>> Hi Paul, >>>>>>>> >>>>>>>> Thanks and that helped. >>>>>>>> >>>>>>>> Where can I find the variables like Turbulent KE , shear stress on >>>>>>>> the wall. ? >>>>>>>> >>>>>>>> Do i have to activate some parameters for calculating them ? >>>>>>>> >>>>>>>> If I had to plot them. >>>>>>>> >>>>>>>> Thanks, >>>>>>>> Kamal >>>>>>>> >>>>>>>> >>>>>>>> On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov >>>>>>>> wrote: >>>>>>>> >>>>>>>>> Kamal, >>>>>>>>> >>>>>>>>> Looks good. >>>>>>>>> >>>>>>>>> I'm guessing that one further refinement would be: >>>>>>>>> >>>>>>>>> if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) >>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>> >>>>>>>>> which would yield >>>>>>>>> >>>>>>>>> scale = 1 when z=z0 >>>>>>>>> scale = smax when z >= z1 >>>>>>>>> >>>>>>>>> Paul >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>> >>>>>>>>>> Hi paul, >>>>>>>>>> >>>>>>>>>> The code works fine, but there should be a small change thats >>>>>>>>>> has >>>>>>>>>> to be done >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>> >>>>>>>>>> This creates a perfect diverging pipe. >>>>>>>>>> >>>>>>>>>> Thanks for the help paul. >>>>>>>>>> >>>>>>>>>> Kamal >>>>>>>>>> >>>>>>>>>> On Jan 20, 2014, at 12:09 AM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>> wrote: >>>>>>>>>> >>>>>>>>>>> Hi paul, >>>>>>>>>>> >>>>>>>>>>> If I am not wrong, >>>>>>>>>>> I make a mesh with three straight pipes( inlet, divergent, >>>>>>>>>>> outlet ) connected together via n2to3 so that I know the >>>>>>>>>>> element >>>>>>>>>>> connectivity places of the divergent section (z0,z1) and use >>>>>>>>>>> the >>>>>>>>>>> section what you gave >>>>>>>>>>> >>>>>>>>>>> Thank you for the code >>>>>>>>>>> >>>>>>>>>>> Kamal >>>>>>>>>>> >>>>>>>>>>> On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> wrote: >>>>>>>>>>> >>>>>>>>>>>> Kamal, >>>>>>>>>>>> >>>>>>>>>>>> I would do the following in usrdat2(): >>>>>>>>>>>> >>>>>>>>>>>> n=nx1*ny1*nz1*nelt >>>>>>>>>>>> >>>>>>>>>>>> do i=1,n >>>>>>>>>>>> x=xm1(i,1,1,1) >>>>>>>>>>>> y=ym1(i,1,1,1) >>>>>>>>>>>> z=ym1(i,1,1,1) >>>>>>>>>>>> scale = 1. >>>>>>>>>>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>>>> xm1(i,1,1,1) = scale*x >>>>>>>>>>>> ym1(i,1,1,1) = scale*y >>>>>>>>>>>> enddo >>>>>>>>>>>> >>>>>>>>>>>> Paul >>>>>>>>>>>> >>>>>>>>>>>> Make certain that z1 and z0 correspond to z values >>>>>>>>>>>> that precisely coincide with element interfaces. >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>> >>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>> >>>>>>>>>>>>> I looked into the Peris example but It is so what same like >>>>>>>>>>>>> the stenosis example with a Cosine deformation. >>>>>>>>>>>>> >>>>>>>>>>>>> In my case it is a pipe with conical divergent. I tried to >>>>>>>>>>>>> play around the variables Xm1, Ym1 and Zm1 but the mapping >>>>>>>>>>>>> doesn't go well. >>>>>>>>>>>>> >>>>>>>>>>>>> Could you please help me with this. >>>>>>>>>>>>> >>>>>>>>>>>>> Thank you, >>>>>>>>>>>>> >>>>>>>>>>>>> Kamal >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> wrote: >>>>>>>>>>>>> >>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> I looked at the Helix and stenosis example but they are >>>>>>>>>>>>>> using >>>>>>>>>>>>>> cosine functions to deform >>>>>>>>>>>>>> >>>>>>>>>>>>>> I tried to use a tangent function but it bends the whole >>>>>>>>>>>>>> pipe. >>>>>>>>>>>>>> >>>>>>>>>>>>>> I dint look at peris example . >>>>>>>>>>>>>> >>>>>>>>>>>>>> I will take a look at it and let you know. >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Have you looked at the peris example? The usr file there >>>>>>>>>>>>>>> shows how to deform >>>>>>>>>>>>>>> a pipe geometry. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Dear Paul, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I tried many ways to map my straight pipe geometry but it >>>>>>>>>>>>>>> does not seem to work properly >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I used something like >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> X = X + Z * tan ( alpha ) >>>>>>>>>>>>>>> Y = Y + Z* tan (alpha ) >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> even that dint work. could please help me with this >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Kamal. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> On Jan 17, 2014, at 2:24 PM, >>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thanks paul. I tried working with the diverging mesh >>>>>>>>>>>>>>>> modification. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> z = mx + b >>>>>>>>>>>>>>>> z = ny + c >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> x = ( z - b ) / m >>>>>>>>>>>>>>>> y = (z - c) / n >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Do you think would work ? or is there any other way to >>>>>>>>>>>>>>>> input that ? >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> 1) To check for convergence, run your simulation for >>>>>>>>>>>>>>>>> increasing polynomial orders ( lx1 in the SIZE file) and >>>>>>>>>>>>>>>>> measure some consistent quantity (drag, TKE, etc). You >>>>>>>>>>>>>>>>> can plot this quantity against lx1 and this should give >>>>>>>>>>>>>>>>> you a good picture of how you are converging (without >>>>>>>>>>>>>>>>> needing to change the physical mesh). >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> 2) If you weren't using temperature in your simulation, >>>>>>>>>>>>>>>>> you could do put the following code snippet in your >>>>>>>>>>>>>>>>> userchk >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>>>> integer i, ntot >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in >>>>>>>>>>>>>>>>> simulation (on THIS processor) >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> do i = 1,ntot >>>>>>>>>>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + >>>>>>>>>>>>>>>>> vz(i,1,1,1)**2) >>>>>>>>>>>>>>>>> enddo >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> ifto = .true. >>>>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I've assumed here that your density is unity. This >>>>>>>>>>>>>>>>> computed kinetic energy point-wise and stores it in the >>>>>>>>>>>>>>>>> temperature field. The part "ifto = .true." tells Nek to >>>>>>>>>>>>>>>>> output the temperature field whenever it outputs a field >>>>>>>>>>>>>>>>> file. You could then view this in visit just like you >>>>>>>>>>>>>>>>> would the velocity field. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Hope this helps! >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Josh >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, >>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I will try that mapping, I created a straight pipe to do >>>>>>>>>>>>>>>>> some simulations. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> 1) Is there a way to check my spectral convergence, so >>>>>>>>>>>>>>>>> that I can do some mesh convergence study? >>>>>>>>>>>>>>>>> 2) Is there a way to plot the kinetic energy in the >>>>>>>>>>>>>>>>> flow ? >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Hi Kamal, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> For the geometry you describe, I would apply mesh >>>>>>>>>>>>>>>>> morphing >>>>>>>>>>>>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>>>>>>>>>>>> using a subset of the mkmesh script provided in the >>>>>>>>>>>>>>>>> expansion >>>>>>>>>>>>>>>>> example. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>>>>>>>>>> certain that the change in slope occurs at element >>>>>>>>>>>>>>>>> boundaries, >>>>>>>>>>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> _______________ >>>>>>>>>>>>>>>>> /| | | >>>>>>>>>>>>>>>>> / | | | >>>>>>>>>>>>>>>>> /| | | | >>>>>>>>>>>>>>>>> ________________/ | | | | >>>>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I looked at the example and it looks very helpful, but >>>>>>>>>>>>>>>>> for >>>>>>>>>>>>>>>>> a sudden expansion we have only two parts (i.e) the inlet >>>>>>>>>>>>>>>>> pipe and the outlet pipe. Whereas in a diverging pipe we >>>>>>>>>>>>>>>>> have three section (i.e,) The inlet pipe, Diverging >>>>>>>>>>>>>>>>> section and the outlet pipe. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Is it possible for me to create a 2D diverging section >>>>>>>>>>>>>>>>> using mesh modification and revolve it around the centre >>>>>>>>>>>>>>>>> axis to get a 3d diverging pipe ? >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> or should I apply the mesh modification directly to >>>>>>>>>>>>>>>>> the 3d >>>>>>>>>>>>>>>>> sudden expansion pipe using usrdat2() ? >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Thanks a lot for the update. I will take a look at as >>>>>>>>>>>>>>>>> soon >>>>>>>>>>>>>>>>> as possible and keep you updated with it. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> On Jan 14, 2014, at 9:04 PM, >>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I've added an example for a step-type expansion in a >>>>>>>>>>>>>>>>> pipe. >>>>>>>>>>>>>>>>> New example directory >>>>>>>>>>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> If you want a standard diffuser, I would use >>>>>>>>>>>>>>>>> mesh-morphing, as outlined in the >>>>>>>>>>>>>>>>> nek primer, which can be found on this page: >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I've also automated our turbulent outflow bc treatment -- >>>>>>>>>>>>>>>>> one simply provides an >>>>>>>>>>>>>>>>> expansion factor (typically ~ 1.5) and two persistent >>>>>>>>>>>>>>>>> arrays to turb_outflow(), which >>>>>>>>>>>>>>>>> is now in navier5.f. This can be useful when very >>>>>>>>>>>>>>>>> strong vortices are leaving the >>>>>>>>>>>>>>>>> domain, which is possible for certain diffuser flow >>>>>>>>>>>>>>>>> conditions (and others). >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>>> ________________________________________ >>>>>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf >>>>>>>>>>>>>>>>> ofnek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Hi >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Can some one please help me in this because I am new >>>>>>>>>>>>>>>>> to nek >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> 1) How can I create a .rea for a specific geometry say >>>>>>>>>>>>>>>>> ' A >>>>>>>>>>>>>>>>> sudden >>>>>>>>>>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> kamal >>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> -- >>>>>>>>>>>>>>>>> Josh Camp >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> "All that is necessary for the triumph of evil is that >>>>>>>>>>>>>>>>> good men do nothing" -- Edmund Burke >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> > > On Fri, 24 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > >> Hello Paul, >> >> Thanks for your reply. I am looking into the .usr file for defining >> the set_obj (). >> >> 1) Could you please tell me what is 'Enter the number of levels ?' in >> n2to3 >> >> is it the number of elements in Z direction ? >> >> 2) As you said about storing the computed vorticity in velocity field >> to view in VisIT, I found the routine to compute the vorticity but I >> am stuck about adding it to the velocity filed to VisIT ? could you >> please tell me how it works or any example which stores vorticity to >> the .fld file as a separate variable. >> >> >> Thank you >> >> Kamal >> >> >> On 22/01/2014 16:53, nek5000-users at lists.mcs.anl.gov wrote: >>> Axial viscous stress is given by torq_calc -- that's no problem >>> whatsoever. You get a number as a >>> function of time. >>> >>> You can even get stresses on multiple subsets of the geometry (e.g., >>> if you had multiple branches >>> in the domain or multiple cylinders. The drag, which is a >>> byproduct of the torque computation (which >>> you can ignore), is given in terms of the viscous and pressure >>> components separately and as the >>> sum of the two. >>> >>> You can identify domain boundaries by checking the boundary >>> conditions. Here, I recommend >>> looking at the set_obj routines in several of the /example cases. >>> >>> >>> ________________________________________ >>> From: nek5000-users-bounces at lists.mcs.anl.gov >>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>> Sent: Wednesday, January 22, 2014 9:37 AM >>> To: nek5000-users at lists.mcs.anl.gov >>> Subject: Re: [Nek5000-users] Pipe with expansion >>> >>> Hello Paul >>> >>> I was thinking about taking the tangential velocity near to the wall >>> so that I can figure out my length of the recirculation region. >>> >>> Is it possible for me to access the boundary elements of the mesh >>> ??? so that I can take the boundary element and then obtain the >>> velocity at that point so that I can figure out the length of my >>> recirculation region. >>> >>> or take the *.fld file and read it to plot the datas I need. >>> >>> >>> I also want to calculate the axial viscous force acting on the >>> entire pipe. >>> >>> which is given by >>> >>> C_v = F^v / ( d^2 * rho * U^2 ) = double integral ( 1/Re * (du / >>> dr) ) dtheta dz >>> >>> >>> On Jan 22, 2014, at 4:07 PM, nek5000-users at lists.mcs.anl.gov wrote: >>> >>>> Hi Kamal, >>>> >>>> As I thought about it some more, if you're interested in the local >>>> wall shear stress >>>> magnitude I'm quite certain you can get this by plotting the >>>> magnitude of vorticity >>>> on the surface in question. (Note that the sign of the WSS, which >>>> in fact is a tensor >>>> or a vector when restricted to a given surface, is lost in this >>>> process, but that might >>>> not be relevant for your needs.) If that works, then you can >>>> readily compute the >>>> vorticity using one of the routines in nek and store the result in >>>> a velocity field, then >>>> view that field with VisIt. Of course WSS will require >>>> multiplication by viscosity. >>>> >>>> hth, >>>> >>>> Paul >>>> >>>> ________________________________________ >>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>> Sent: Tuesday, January 21, 2014 10:33 AM >>>> To: nek5000-users at lists.mcs.anl.gov >>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>> >>>> Hi paul, >>>> >>>> can I make this to be drag or shear quantities to be return to the a >>>> separate file so that it will easy for me to plot. >>>> >>>> By the way it gives the integral quantity. Think for example I need to >>>> find the shear stress on the wall from the inlet to outlet at a >>>> particular time = 2 . How can I do that ? >>>> >>>> Is there way to find the number of elements in x,y and z direction ? >>>> >>>> On 21/01/2014 17:32, nek5000-users at lists.mcs.anl.gov wrote: >>>>> Hi Kamal, >>>>> >>>>> Your integrated drag quantities should be written to the logfile >>>>> (stdout), >>>>> assuming you've set the arguments in the call to be .true. >>>>> >>>>> Paul >>>>> >>>>> On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>>> Hi Paul, >>>>>> >>>>>> I checked the set_obj subroutine and implemented one in my .USR >>>>>> file. >>>>>> The code seem to run without any errors but I don't find where these >>>>>> variables are getting stored. >>>>>> >>>>>> I use VisIT to visualize my output, even there was no change in it. >>>>>> >>>>>> do I have to define my own output file and write the variables out ? >>>>>> >>>>>> Thanks, >>>>>> >>>>>> Kamal. >>>>>> >>>>>> >>>>>> On 20/01/2014 21:52, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> Hi Kamal, >>>>>>> >>>>>>> You'll need to compute your own tke by manipulating the >>>>>>> velocity fields. >>>>>>> >>>>>>> You can get running averages of the requisite quantities >>>>>>> via calls to "avg_all" which is found in navier5.f >>>>>>> >>>>>>> You can compute shear stress on the wall simply by computing >>>>>>> the drag on the wall, which can be done via a call to >>>>>>> torque_calc(), >>>>>>> also found in navier5.f >>>>>>> >>>>>>> If you cd to /examples and type: >>>>>>> >>>>>>> grep torq */*.usr >>>>>>> >>>>>>> you'll find many examples of calls to torque_calc. You simply >>>>>>> need to prescribe the surfaces on which shear is to be integrated. >>>>>>> >>>>>>> I typically write a routine "set_obj" to identify such surfaces >>>>>>> on the first call to usrchk. >>>>>>> >>>>>>> grep set_obj */*.usr >>>>>>> >>>>>>> will show similar examples. >>>>>>> >>>>>>> I would recommend trying this for laminar Poiseiulle flow in >>>>>>> a very simple channel just to check that your calls are properly >>>>>>> set. >>>>>>> >>>>>>> Best, >>>>>>> >>>>>>> Paul >>>>>>> >>>>>>> >>>>>>> On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>>> Hi Paul, >>>>>>>> >>>>>>>> Thanks and that helped. >>>>>>>> >>>>>>>> Where can I find the variables like Turbulent KE , shear stress on >>>>>>>> the wall. ? >>>>>>>> >>>>>>>> Do i have to activate some parameters for calculating them ? >>>>>>>> >>>>>>>> If I had to plot them. >>>>>>>> >>>>>>>> Thanks, >>>>>>>> Kamal >>>>>>>> >>>>>>>> >>>>>>>> On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov >>>>>>>> wrote: >>>>>>>> >>>>>>>>> Kamal, >>>>>>>>> >>>>>>>>> Looks good. >>>>>>>>> >>>>>>>>> I'm guessing that one further refinement would be: >>>>>>>>> >>>>>>>>> if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) >>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>> >>>>>>>>> which would yield >>>>>>>>> >>>>>>>>> scale = 1 when z=z0 >>>>>>>>> scale = smax when z >= z1 >>>>>>>>> >>>>>>>>> Paul >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>> >>>>>>>>>> Hi paul, >>>>>>>>>> >>>>>>>>>> The code works fine, but there should be a small change thats >>>>>>>>>> has >>>>>>>>>> to be done >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>> >>>>>>>>>> This creates a perfect diverging pipe. >>>>>>>>>> >>>>>>>>>> Thanks for the help paul. >>>>>>>>>> >>>>>>>>>> Kamal >>>>>>>>>> >>>>>>>>>> On Jan 20, 2014, at 12:09 AM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>> wrote: >>>>>>>>>> >>>>>>>>>>> Hi paul, >>>>>>>>>>> >>>>>>>>>>> If I am not wrong, >>>>>>>>>>> I make a mesh with three straight pipes( inlet, divergent, >>>>>>>>>>> outlet ) connected together via n2to3 so that I know the >>>>>>>>>>> element >>>>>>>>>>> connectivity places of the divergent section (z0,z1) and use >>>>>>>>>>> the >>>>>>>>>>> section what you gave >>>>>>>>>>> >>>>>>>>>>> Thank you for the code >>>>>>>>>>> >>>>>>>>>>> Kamal >>>>>>>>>>> >>>>>>>>>>> On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> wrote: >>>>>>>>>>> >>>>>>>>>>>> Kamal, >>>>>>>>>>>> >>>>>>>>>>>> I would do the following in usrdat2(): >>>>>>>>>>>> >>>>>>>>>>>> n=nx1*ny1*nz1*nelt >>>>>>>>>>>> >>>>>>>>>>>> do i=1,n >>>>>>>>>>>> x=xm1(i,1,1,1) >>>>>>>>>>>> y=ym1(i,1,1,1) >>>>>>>>>>>> z=ym1(i,1,1,1) >>>>>>>>>>>> scale = 1. >>>>>>>>>>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>>>> xm1(i,1,1,1) = scale*x >>>>>>>>>>>> ym1(i,1,1,1) = scale*y >>>>>>>>>>>> enddo >>>>>>>>>>>> >>>>>>>>>>>> Paul >>>>>>>>>>>> >>>>>>>>>>>> Make certain that z1 and z0 correspond to z values >>>>>>>>>>>> that precisely coincide with element interfaces. >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>> >>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>> >>>>>>>>>>>>> I looked into the Peris example but It is so what same like >>>>>>>>>>>>> the stenosis example with a Cosine deformation. >>>>>>>>>>>>> >>>>>>>>>>>>> In my case it is a pipe with conical divergent. I tried to >>>>>>>>>>>>> play around the variables Xm1, Ym1 and Zm1 but the mapping >>>>>>>>>>>>> doesn't go well. >>>>>>>>>>>>> >>>>>>>>>>>>> Could you please help me with this. >>>>>>>>>>>>> >>>>>>>>>>>>> Thank you, >>>>>>>>>>>>> >>>>>>>>>>>>> Kamal >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> wrote: >>>>>>>>>>>>> >>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> I looked at the Helix and stenosis example but they are >>>>>>>>>>>>>> using >>>>>>>>>>>>>> cosine functions to deform >>>>>>>>>>>>>> >>>>>>>>>>>>>> I tried to use a tangent function but it bends the whole >>>>>>>>>>>>>> pipe. >>>>>>>>>>>>>> >>>>>>>>>>>>>> I dint look at peris example . >>>>>>>>>>>>>> >>>>>>>>>>>>>> I will take a look at it and let you know. >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Have you looked at the peris example? The usr file there >>>>>>>>>>>>>>> shows how to deform >>>>>>>>>>>>>>> a pipe geometry. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Dear Paul, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I tried many ways to map my straight pipe geometry but it >>>>>>>>>>>>>>> does not seem to work properly >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I used something like >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> X = X + Z * tan ( alpha ) >>>>>>>>>>>>>>> Y = Y + Z* tan (alpha ) >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> even that dint work. could please help me with this >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Kamal. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> On Jan 17, 2014, at 2:24 PM, >>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thanks paul. I tried working with the diverging mesh >>>>>>>>>>>>>>>> modification. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> z = mx + b >>>>>>>>>>>>>>>> z = ny + c >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> x = ( z - b ) / m >>>>>>>>>>>>>>>> y = (z - c) / n >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Do you think would work ? or is there any other way to >>>>>>>>>>>>>>>> input that ? >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> 1) To check for convergence, run your simulation for >>>>>>>>>>>>>>>>> increasing polynomial orders ( lx1 in the SIZE file) and >>>>>>>>>>>>>>>>> measure some consistent quantity (drag, TKE, etc). You >>>>>>>>>>>>>>>>> can plot this quantity against lx1 and this should give >>>>>>>>>>>>>>>>> you a good picture of how you are converging (without >>>>>>>>>>>>>>>>> needing to change the physical mesh). >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> 2) If you weren't using temperature in your simulation, >>>>>>>>>>>>>>>>> you could do put the following code snippet in your >>>>>>>>>>>>>>>>> userchk >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>>>> integer i, ntot >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in >>>>>>>>>>>>>>>>> simulation (on THIS processor) >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> do i = 1,ntot >>>>>>>>>>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + >>>>>>>>>>>>>>>>> vz(i,1,1,1)**2) >>>>>>>>>>>>>>>>> enddo >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> ifto = .true. >>>>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I've assumed here that your density is unity. This >>>>>>>>>>>>>>>>> computed kinetic energy point-wise and stores it in the >>>>>>>>>>>>>>>>> temperature field. The part "ifto = .true." tells Nek to >>>>>>>>>>>>>>>>> output the temperature field whenever it outputs a field >>>>>>>>>>>>>>>>> file. You could then view this in visit just like you >>>>>>>>>>>>>>>>> would the velocity field. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Hope this helps! >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Josh >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, >>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I will try that mapping, I created a straight pipe to do >>>>>>>>>>>>>>>>> some simulations. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> 1) Is there a way to check my spectral convergence, so >>>>>>>>>>>>>>>>> that I can do some mesh convergence study? >>>>>>>>>>>>>>>>> 2) Is there a way to plot the kinetic energy in the >>>>>>>>>>>>>>>>> flow ? >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Hi Kamal, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> For the geometry you describe, I would apply mesh >>>>>>>>>>>>>>>>> morphing >>>>>>>>>>>>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>>>>>>>>>>>> using a subset of the mkmesh script provided in the >>>>>>>>>>>>>>>>> expansion >>>>>>>>>>>>>>>>> example. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>>>>>>>>>> certain that the change in slope occurs at element >>>>>>>>>>>>>>>>> boundaries, >>>>>>>>>>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> _______________ >>>>>>>>>>>>>>>>> /| | | >>>>>>>>>>>>>>>>> / | | | >>>>>>>>>>>>>>>>> /| | | | >>>>>>>>>>>>>>>>> ________________/ | | | | >>>>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I looked at the example and it looks very helpful, but >>>>>>>>>>>>>>>>> for >>>>>>>>>>>>>>>>> a sudden expansion we have only two parts (i.e) the inlet >>>>>>>>>>>>>>>>> pipe and the outlet pipe. Whereas in a diverging pipe we >>>>>>>>>>>>>>>>> have three section (i.e,) The inlet pipe, Diverging >>>>>>>>>>>>>>>>> section and the outlet pipe. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Is it possible for me to create a 2D diverging section >>>>>>>>>>>>>>>>> using mesh modification and revolve it around the centre >>>>>>>>>>>>>>>>> axis to get a 3d diverging pipe ? >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> or should I apply the mesh modification directly to >>>>>>>>>>>>>>>>> the 3d >>>>>>>>>>>>>>>>> sudden expansion pipe using usrdat2() ? >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Thanks a lot for the update. I will take a look at as >>>>>>>>>>>>>>>>> soon >>>>>>>>>>>>>>>>> as possible and keep you updated with it. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> On Jan 14, 2014, at 9:04 PM, >>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I've added an example for a step-type expansion in a >>>>>>>>>>>>>>>>> pipe. >>>>>>>>>>>>>>>>> New example directory >>>>>>>>>>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> If you want a standard diffuser, I would use >>>>>>>>>>>>>>>>> mesh-morphing, as outlined in the >>>>>>>>>>>>>>>>> nek primer, which can be found on this page: >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I've also automated our turbulent outflow bc treatment -- >>>>>>>>>>>>>>>>> one simply provides an >>>>>>>>>>>>>>>>> expansion factor (typically ~ 1.5) and two persistent >>>>>>>>>>>>>>>>> arrays to turb_outflow(), which >>>>>>>>>>>>>>>>> is now in navier5.f. This can be useful when very >>>>>>>>>>>>>>>>> strong vortices are leaving the >>>>>>>>>>>>>>>>> domain, which is possible for certain diffuser flow >>>>>>>>>>>>>>>>> conditions (and others). >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>>> ________________________________________ >>>>>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf >>>>>>>>>>>>>>>>> ofnek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Hi >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Can some one please help me in this because I am new >>>>>>>>>>>>>>>>> to nek >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> 1) How can I create a .rea for a specific geometry say >>>>>>>>>>>>>>>>> ' A >>>>>>>>>>>>>>>>> sudden >>>>>>>>>>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> kamal >>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> -- >>>>>>>>>>>>>>>>> Josh Camp >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> "All that is necessary for the triumph of evil is that >>>>>>>>>>>>>>>>> good men do nothing" -- Edmund Burke >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users -------------- next part -------------- c----------------------------------------------------------------------- C C USER SPECIFIED ROUTINES: C C - boundary conditions C - initial conditions C - variable properties C - local acceleration for fluid (a) C - forcing function for passive scalar (q) C - general purpose routine for checking errors etc. C c----------------------------------------------------------------------- subroutine uservp (ix,iy,iz,eg) include 'SIZE' include 'TOTAL' include 'NEKUSE' integer e,f,eg c e = gllel(eg) udiff =0. utrans=0. return end c----------------------------------------------------------------------- subroutine userf (ix,iy,iz,eg) include 'SIZE' include 'TOTAL' include 'NEKUSE' integer e,f,eg c e = gllel(eg) c Note: this is an acceleration term, NOT a force! c Thus, ffx will subsequently be multiplied by rho(x,t). ffx = 0.0 ffy = 0.0 ffz = 0.0 return end c----------------------------------------------------------------------- subroutine userq (ix,iy,iz,eg) include 'SIZE' include 'TOTAL' include 'NEKUSE' integer e,f,eg c e = gllel(eg) qvol = 0.0 source = 0.0 return end c----------------------------------------------------------------------- subroutine userchk include 'SIZE' include 'TOTAL' parameter (lt=lx1*ly1*lz1*lelt) common /myjunk/ vort(lt,3),w11(lt),w21(lt) common /myoutflow/ d(lx1*ly1*lz1*lelt),w1(lx1*ly1*lz1*lelt) n = nx1*ny1*nz1*nelv wmax = glmax(vz,n) ubar = 0. uarea = 0. do e=1,nelv do f=1,2*ndim if (cbc(f,e,1).eq.'v ') then call surface_int(uint,aint,vz,e,f) ubar = ubar + uint uarea = uarea + aint endif enddo enddo ubar = glsum(ubar ,1) uarea = glsum(uarea,1) if (uarea.gt.0) ubar = ubar/uarea if (nid.eq.0) write(6,1) istep,time,uarea,ubar,wmax 1 format(i9,1p4e12.4,' ubar') if (istep.eq.0) call set_obj if (mod(istep,100).eq.0) call avg_all if (mod(istep,100).eq.0) call torque_calc(1.0,x0,.false.,.true.) if (mod(istep,iostep).eq.0) then call comp_vort3(vort,w11,w21,vx,vy,vz) call outpost(vort(1,1),vort(1,2),vort(1,3),pr,t,'vrt') end if c ifxyo = .true. if (iostep.gt.0.and.istep.gt.iostep) ifxyo = .false. return end c----------------------------------------------------------------------- subroutine userbc (ix,iy,iz,iside,ieg) include 'SIZE' include 'TOTAL' include 'NEKUSE' integer e,eg common /mygeom/ xmin,xmax,ymin,ymax delta = 1 if (z.le.0) delta = 0.5 xd=x/delta yd=y/delta rr=xd*xd+yd*yd scale = 2*(0.5/delta)**2 ! Ubar = 1 in inlet pipe (r=0.5) ux=0.0 uy=0.0 uz=scale*(1-rr) temp=0.0 return end c----------------------------------------------------------------------- subroutine useric (ix,iy,iz,ieg) include 'SIZE' include 'TOTAL' include 'NEKUSE' integer e,eg delta = 1 if (z.le.0) delta = 0.5 xd=x/delta yd=y/delta rr=xd*xd+yd*yd scale = 2*(0.5/delta)**2 ! Ubar = 1 in inlet pipe (r=0.5) ux=0.0 uy=0.0 uz=scale*(1-rr) temp=0.0 return end c----------------------------------------------------------------------- subroutine usrdat include 'SIZE' include 'TOTAL' c return end c----------------------------------------------------------------------- subroutine usrdat3 include 'SIZE' include 'TOTAL' c return end c----------------------------------------------------------------------- subroutine usrdat2 ! Modify geometry include 'SIZE' include 'TOTAL' common /mygeom/ xmin,xmax,ymin,ymax n = nx1*ny1*nz1*nelt scal = 0.5 ! Rescale radius from 1.0 to 0.5 call cmult(xm1,scal,n) call cmult(ym1,scal,n) xmin = glmin(xm1,n) ymin = glmin(ym1,n) xmax = glmax(xm1,n) ymax = glmax(ym1,n) smax = 2.0 z0 = 0. z1 = 1. do i=1,n x = xm1(i,1,1,1) y = ym1(i,1,1,1) z = zm1(i,1,1,1) scale = 1. if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) if (z.gt.z1) scale = smax xm1(i,1,1,1) = scale*x ym1(i,1,1,1) = scale*y enddo param(59) = 1 ! Force ifdfrm=.true. ( 8/26/03 ) ifxyo = .true. c call outpost(xm1,ym1,zm1,pr,t,' ') c call exitt return end c----------------------------------------------------------------------- subroutine set_obj ! define objects for surface integrals c include 'SIZE' include 'TOTAL' c integer e,f c c Define new objects c nobj = 1 ! for Periodic iobj = 0 do ii=nhis+1,nhis+nobj iobj = iobj+1 hcode(10,ii) = 'I' hcode( 1,ii) = 'F' ! 'F' hcode( 2,ii) = 'F' ! 'F' hcode( 3,ii) = 'F' ! 'F' lochis(1,ii) = iobj enddo nhis = nhis + nobj c if (maxobj.lt.nobj) write(6,*) 'increase maxobj in SIZEu. rm *.o' if (maxobj.lt.nobj) call exitt c nxyz = nx1*ny1*nz1 do e=1,nelv do f=1,2*ndim if (cbc(f,e,1).eq.'W ') then iobj = 1 if (iobj.gt.0) then nmember(iobj) = nmember(iobj) + 1 mem = nmember(iobj) ieg = lglel(e) object(iobj,mem,1) = ieg object(iobj,mem,2) = f c write(6,1) iobj,mem,f,ieg,e,nid,' OBJ' 1 format(6i9,a4) endif c endif enddo enddo c write(6,*) 'number',(nmember(k),k=1,4) c return end From nek5000-users at lists.mcs.anl.gov Thu Jan 30 05:06:08 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Thu, 30 Jan 2014 12:06:08 +0100 Subject: [Nek5000-users] Linearised Navier-Stokes time-dependant base flow Message-ID: Hi Nek's, I have a question regarding the linearised Navier-Stokes solver while the underlying base flow is time-dependant. As far as I understand, one should simply have to set param(31) = 1 to achieve this (and p31 = -1 for a steady state base flow). What about the boundary conditions however? For instant, I want to investigate the linear dynamics of perturbations evolving onto a lid-driven cavity flow exhibiting a periodic limit cycle I have computed. How could I impose in userbc: ux = 1 uy = 0 uz = 0 for the periodic base flow time-evolution, and in the meantime: ux = 0 uy = 0 uz = 0 for the perturbation? Cheers, JC -- Jean-Christophe Loiseau Homepage -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Thu Jan 30 05:18:43 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Thu, 30 Jan 2014 05:18:43 -0600 (CST) Subject: [Nek5000-users] NEK5000 User Group Metting In-Reply-To: References: Message-ID: Dear Murph & all, We're presently firming up dates and should be making an announcement soon. Paul On Tue, 28 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > Hi All, > > Is there any more info on the possibility of a User Group Meeting this year? > > Thanks, > Murph > > -- > > > /Confidentiality Notice: I swear and affirm that I will not retransmit, > discuss, or disseminate any information in this message to anyone other than > the intended recipients.However, at this very second, every entity in the > known universe is reading this message.This includes the US Government, > Foreign Governments, all telecommunications carriers, all Internet service > companies, anyone buying adds from said service companies, most major > hardware and software vendors, all hackers and kiddie-scripters older than > about 6, and any space aliens within subspace communications range of > Earth.Tin Foil Helmets do not work./ > > ** > > *Murphy Leo O'Dea, PE"Murph"* > > PhD Student, Mechanical Engineering > > /School Of Engineering And Computer Science/ > > /Oakland University/ > > mlodea at oakland.edu > > http://www.secs.oakland.edu/~mlodea/ > > From nek5000-users at lists.mcs.anl.gov Thu Jan 30 05:27:38 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Thu, 30 Jan 2014 05:27:38 -0600 (CST) Subject: [Nek5000-users] Linearised Navier-Stokes time-dependant base flow In-Reply-To: References: Message-ID: Dear JP, In perturb.f, the driver reads: do jp=1,npert if (nid.eq.0.and.igeom.eq.2) write(6,1) istep,time,jp 1 format(i9,1pe14.7,' Perturbation Solve:',i5) call perturbv (igeom) enddo jp=0 ! set jp to zero, for baseline flow So, the appropriate discriminator in userbc would be: if (jp.eq.0) then ux=1 else ux=0 end Best regards, Paul On Thu, 30 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > Hi Nek's, > > I have a question regarding the linearised Navier-Stokes solver while the > underlying base flow is time-dependant. As far as I understand, one should > simply have to set param(31) = 1 to achieve this (and p31 = -1 for a steady > state base flow). What about the boundary conditions however? > > For instant, I want to investigate the linear dynamics of perturbations > evolving onto a lid-driven cavity flow exhibiting a periodic limit cycle I > have computed. How could I impose in userbc: > > ux = 1 > uy = 0 > uz = 0 > > for the periodic base flow time-evolution, and in the meantime: > > ux = 0 > uy = 0 > uz = 0 > > for the perturbation? > > Cheers, > JC > > -- > Jean-Christophe Loiseau > Homepage > From nek5000-users at lists.mcs.anl.gov Thu Jan 30 06:13:52 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Thu, 30 Jan 2014 13:13:52 +0100 Subject: [Nek5000-users] Linearised Navier-Stokes time-dependant base flow In-Reply-To: References: Message-ID: Thanks a lot Paul. That's pretty much the idea I had, but I just wanted to make sure. Regards, JC 2014-01-30 : > > Dear JP, > > In perturb.f, the driver reads: > > do jp=1,npert > > if (nid.eq.0.and.igeom.eq.2) write(6,1) istep,time,jp > 1 format(i9,1pe14.7,' Perturbation Solve:',i5) > > call perturbv (igeom) > > enddo > > jp=0 ! set jp to zero, for baseline flow > > > So, the appropriate discriminator in userbc would be: > > if (jp.eq.0) then > > ux=1 > > else > > ux=0 > > end > > Best regards, > > Paul > > > > > > On Thu, 30 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > > Hi Nek's, >> >> I have a question regarding the linearised Navier-Stokes solver while the >> underlying base flow is time-dependant. As far as I understand, one should >> simply have to set param(31) = 1 to achieve this (and p31 = -1 for a >> steady >> state base flow). What about the boundary conditions however? >> >> For instant, I want to investigate the linear dynamics of perturbations >> evolving onto a lid-driven cavity flow exhibiting a periodic limit cycle I >> have computed. How could I impose in userbc: >> >> ux = 1 >> uy = 0 >> uz = 0 >> >> for the periodic base flow time-evolution, and in the meantime: >> >> ux = 0 >> uy = 0 >> uz = 0 >> >> for the perturbation? >> >> Cheers, >> JC >> >> -- >> Jean-Christophe Loiseau >> Homepage >> >> _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > -- Jean-Christophe Loiseau Homepage -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Fri Jan 31 05:16:01 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Fri, 31 Jan 2014 13:16:01 +0200 Subject: [Nek5000-users] questions about DNS/LES, variable time stepping, mesh generation In-Reply-To: References: Message-ID: Dear Nek's, 1. How to do LES or DNS? 2. How to do variable time stepping? 3. How to build a mesh for conic shape instead the cylindrical one given in turboJet? Thanks in advance, Barak From nek5000-users at lists.mcs.anl.gov Fri Jan 31 08:10:48 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Fri, 31 Jan 2014 15:10:48 +0100 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , , Message-ID: Hi Neks, I tried to simulated steady flow by setting the logical operator IFTRAN = F but the simulation still runs in transient mode, How do I get a steady time independent solution so that I can use it as my Initial Condition ? Thank you, Kamal On 29/01/2014 16:01, nek5000-users at lists.mcs.anl.gov wrote: > Hello Paul, > > Thanks for the vorticity output and it worked. > > > 1) I created a set-obj() for my pipe but how can I be sure that it has > taken the full pipe wall surface in to account ? > I have attached the divpipe.usr file for your reference could you > please take a look at it. > > 2) I even took torque_calc in to the .usr file and it gives out > something like this > > 200 1.00000000000E+00 -9.76942759878E-06 -8.98721249598E-06 > -7.82215102801E-07 1torqx > 200 1.00000000000E+00 -6.69169235606E-06 -6.35251009840E-06 > -3.39182257669E-07 1torqy > 200 1.00000000000E+00 9.50518561890E-10 1.50349344990E-13 > 9.50368212545E-10 1torqz > > if I am not wrong are these the value of surface integral of viscous > force in three components of velocity along three directions taken in > the set_obj() ? > > because I would like to calculate this > > C_v = F^v / ( d^2 * rho * U^2 ) = double integral ( 1/Re * (du / > dr) ) dtheta dz > > > Thank you, > > Kamal. > > > On 24/01/2014 13:02, nek5000-users at lists.mcs.anl.gov wrote: >> >> >> >> Kamal, >> >> 1) yes >> >> 2) standard approach to seeing vorticity would be something >> like the following in userchk >> >> parameter (lt=lx1*ly1*lz1*lelt) >> common /myjunk/ vort(lt,3),w1(lt),w2(lt) >> logical ifxyt >> integer ivout ! flag to turn geometry on/off for VisIt >> save ivout >> data ivout /0/ >> >> >> if (mod(istep,iostep).eq.0) then >> call comp_vort3(vort,w1,w2,vx,vy,vz) >> >> ifxyt = ifxyo ! put geometry into first vrt file >> ifxyo = .false. >> if (ivout.eq.0) ifxyo = .true. >> ivout = 1 >> >> call outpost(vort(1,1),vort(1,2),vort(1,3),pr,t,'vrt') >> >> ifxyo = ifxyt ! restore ifxyo flag to original state >> >> endif >> >> >> If your session name is blah, this piece of code will put >> vorticity into a sequence of files vrtblah0.f0000n >> >> You can instead ignore the vrt prefix and the part about the >> geometry with a simpler code >> >> parameter (lt=lx1*ly1*lz1*lelt) >> common /myjunk/ vort(lt,3),w1(lt),w2(lt) >> >> if (mod(istep,iostep).eq.0) then >> call comp_vort3(vort,w1,w2,vx,vy,vz) >> call outpost(vort(1,1),vort(1,2),vort(1,3),pr,t,'vrt') >> endif >> >> I usually go for this latter approach, but the choice is >> totally up to you. >> >> Paul >> >> >> >> >> >> On Fri, 24 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >> >>> Hello Paul, >>> >>> Thanks for your reply. I am looking into the .usr file for defining >>> the set_obj (). >>> >>> 1) Could you please tell me what is 'Enter the number of levels ?' >>> in n2to3 >>> >>> is it the number of elements in Z direction ? >>> >>> 2) As you said about storing the computed vorticity in velocity >>> field to view in VisIT, I found the routine to compute the vorticity >>> but I am stuck about adding it to the velocity filed to VisIT ? >>> could you please tell me how it works or any example which stores >>> vorticity to the .fld file as a separate variable. >>> >>> >>> Thank you >>> >>> Kamal >>> >>> >>> On 22/01/2014 16:53, nek5000-users at lists.mcs.anl.gov wrote: >>>> Axial viscous stress is given by torq_calc -- that's no problem >>>> whatsoever. You get a number as a >>>> function of time. >>>> >>>> You can even get stresses on multiple subsets of the geometry >>>> (e.g., if you had multiple branches >>>> in the domain or multiple cylinders. The drag, which is a >>>> byproduct of the torque computation (which >>>> you can ignore), is given in terms of the viscous and pressure >>>> components separately and as the >>>> sum of the two. >>>> >>>> You can identify domain boundaries by checking the boundary >>>> conditions. Here, I recommend >>>> looking at the set_obj routines in several of the /example cases. >>>> >>>> >>>> ________________________________________ >>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>> Sent: Wednesday, January 22, 2014 9:37 AM >>>> To: nek5000-users at lists.mcs.anl.gov >>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>> >>>> Hello Paul >>>> >>>> I was thinking about taking the tangential velocity near to the >>>> wall so that I can figure out my length of the recirculation region. >>>> >>>> Is it possible for me to access the boundary elements of the mesh >>>> ??? so that I can take the boundary element and then obtain the >>>> velocity at that point so that I can figure out the length of my >>>> recirculation region. >>>> >>>> or take the *.fld file and read it to plot the datas I need. >>>> >>>> >>>> I also want to calculate the axial viscous force acting on the >>>> entire pipe. >>>> >>>> which is given by >>>> >>>> C_v = F^v / ( d^2 * rho * U^2 ) = double integral ( 1/Re * (du / >>>> dr) ) dtheta dz >>>> >>>> >>>> On Jan 22, 2014, at 4:07 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> Hi Kamal, >>>>> >>>>> As I thought about it some more, if you're interested in the local >>>>> wall shear stress >>>>> magnitude I'm quite certain you can get this by plotting the >>>>> magnitude of vorticity >>>>> on the surface in question. (Note that the sign of the WSS, >>>>> which in fact is a tensor >>>>> or a vector when restricted to a given surface, is lost in this >>>>> process, but that might >>>>> not be relevant for your needs.) If that works, then you can >>>>> readily compute the >>>>> vorticity using one of the routines in nek and store the result in >>>>> a velocity field, then >>>>> view that field with VisIt. Of course WSS will require >>>>> multiplication by viscosity. >>>>> >>>>> hth, >>>>> >>>>> Paul >>>>> >>>>> ________________________________________ >>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>> Sent: Tuesday, January 21, 2014 10:33 AM >>>>> To: nek5000-users at lists.mcs.anl.gov >>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>> >>>>> Hi paul, >>>>> >>>>> can I make this to be drag or shear quantities to be return to the a >>>>> separate file so that it will easy for me to plot. >>>>> >>>>> By the way it gives the integral quantity. Think for example I >>>>> need to >>>>> find the shear stress on the wall from the inlet to outlet at a >>>>> particular time = 2 . How can I do that ? >>>>> >>>>> Is there way to find the number of elements in x,y and z direction ? >>>>> >>>>> On 21/01/2014 17:32, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> Hi Kamal, >>>>>> >>>>>> Your integrated drag quantities should be written to the logfile >>>>>> (stdout), >>>>>> assuming you've set the arguments in the call to be .true. >>>>>> >>>>>> Paul >>>>>> >>>>>> On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>>> Hi Paul, >>>>>>> >>>>>>> I checked the set_obj subroutine and implemented one in my .USR >>>>>>> file. >>>>>>> The code seem to run without any errors but I don't find where >>>>>>> these >>>>>>> variables are getting stored. >>>>>>> >>>>>>> I use VisIT to visualize my output, even there was no change in it. >>>>>>> >>>>>>> do I have to define my own output file and write the variables >>>>>>> out ? >>>>>>> >>>>>>> Thanks, >>>>>>> >>>>>>> Kamal. >>>>>>> >>>>>>> >>>>>>> On 20/01/2014 21:52, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> Hi Kamal, >>>>>>>> >>>>>>>> You'll need to compute your own tke by manipulating the >>>>>>>> velocity fields. >>>>>>>> >>>>>>>> You can get running averages of the requisite quantities >>>>>>>> via calls to "avg_all" which is found in navier5.f >>>>>>>> >>>>>>>> You can compute shear stress on the wall simply by computing >>>>>>>> the drag on the wall, which can be done via a call to >>>>>>>> torque_calc(), >>>>>>>> also found in navier5.f >>>>>>>> >>>>>>>> If you cd to /examples and type: >>>>>>>> >>>>>>>> grep torq */*.usr >>>>>>>> >>>>>>>> you'll find many examples of calls to torque_calc. You simply >>>>>>>> need to prescribe the surfaces on which shear is to be integrated. >>>>>>>> >>>>>>>> I typically write a routine "set_obj" to identify such surfaces >>>>>>>> on the first call to usrchk. >>>>>>>> >>>>>>>> grep set_obj */*.usr >>>>>>>> >>>>>>>> will show similar examples. >>>>>>>> >>>>>>>> I would recommend trying this for laminar Poiseiulle flow in >>>>>>>> a very simple channel just to check that your calls are properly >>>>>>>> set. >>>>>>>> >>>>>>>> Best, >>>>>>>> >>>>>>>> Paul >>>>>>>> >>>>>>>> >>>>>>>> On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> >>>>>>>>> Hi Paul, >>>>>>>>> >>>>>>>>> Thanks and that helped. >>>>>>>>> >>>>>>>>> Where can I find the variables like Turbulent KE , shear >>>>>>>>> stress on >>>>>>>>> the wall. ? >>>>>>>>> >>>>>>>>> Do i have to activate some parameters for calculating them ? >>>>>>>>> >>>>>>>>> If I had to plot them. >>>>>>>>> >>>>>>>>> Thanks, >>>>>>>>> Kamal >>>>>>>>> >>>>>>>>> >>>>>>>>> On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov >>>>>>>>> wrote: >>>>>>>>> >>>>>>>>>> Kamal, >>>>>>>>>> >>>>>>>>>> Looks good. >>>>>>>>>> >>>>>>>>>> I'm guessing that one further refinement would be: >>>>>>>>>> >>>>>>>>>> if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) >>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>> >>>>>>>>>> which would yield >>>>>>>>>> >>>>>>>>>> scale = 1 when z=z0 >>>>>>>>>> scale = smax when z >= z1 >>>>>>>>>> >>>>>>>>>> Paul >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>> >>>>>>>>>>> Hi paul, >>>>>>>>>>> >>>>>>>>>>> The code works fine, but there should be a small change >>>>>>>>>>> thats has >>>>>>>>>>> to be done >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >>>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>>> >>>>>>>>>>> This creates a perfect diverging pipe. >>>>>>>>>>> >>>>>>>>>>> Thanks for the help paul. >>>>>>>>>>> >>>>>>>>>>> Kamal >>>>>>>>>>> >>>>>>>>>>> On Jan 20, 2014, at 12:09 AM, >>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>> >>>>>>>>>>>> Hi paul, >>>>>>>>>>>> >>>>>>>>>>>> If I am not wrong, >>>>>>>>>>>> I make a mesh with three straight pipes( inlet, divergent, >>>>>>>>>>>> outlet ) connected together via n2to3 so that I know the >>>>>>>>>>>> element >>>>>>>>>>>> connectivity places of the divergent section (z0,z1) and >>>>>>>>>>>> use the >>>>>>>>>>>> section what you gave >>>>>>>>>>>> >>>>>>>>>>>> Thank you for the code >>>>>>>>>>>> >>>>>>>>>>>> Kamal >>>>>>>>>>>> >>>>>>>>>>>> On Jan 19, 2014, at 8:45 PM, >>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>> >>>>>>>>>>>>> Kamal, >>>>>>>>>>>>> >>>>>>>>>>>>> I would do the following in usrdat2(): >>>>>>>>>>>>> >>>>>>>>>>>>> n=nx1*ny1*nz1*nelt >>>>>>>>>>>>> >>>>>>>>>>>>> do i=1,n >>>>>>>>>>>>> x=xm1(i,1,1,1) >>>>>>>>>>>>> y=ym1(i,1,1,1) >>>>>>>>>>>>> z=ym1(i,1,1,1) >>>>>>>>>>>>> scale = 1. >>>>>>>>>>>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>>>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>>>>> xm1(i,1,1,1) = scale*x >>>>>>>>>>>>> ym1(i,1,1,1) = scale*y >>>>>>>>>>>>> enddo >>>>>>>>>>>>> >>>>>>>>>>>>> Paul >>>>>>>>>>>>> >>>>>>>>>>>>> Make certain that z1 and z0 correspond to z values >>>>>>>>>>>>> that precisely coincide with element interfaces. >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>> >>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> I looked into the Peris example but It is so what same like >>>>>>>>>>>>>> the stenosis example with a Cosine deformation. >>>>>>>>>>>>>> >>>>>>>>>>>>>> In my case it is a pipe with conical divergent. I tried to >>>>>>>>>>>>>> play around the variables Xm1, Ym1 and Zm1 but the mapping >>>>>>>>>>>>>> doesn't go well. >>>>>>>>>>>>>> >>>>>>>>>>>>>> Could you please help me with this. >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I looked at the Helix and stenosis example but they are >>>>>>>>>>>>>>> using >>>>>>>>>>>>>>> cosine functions to deform >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I tried to use a tangent function but it bends the whole >>>>>>>>>>>>>>> pipe. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I dint look at peris example . >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I will take a look at it and let you know. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> On Jan 18, 2014, at 7:22 PM, >>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Have you looked at the peris example? The usr file there >>>>>>>>>>>>>>>> shows how to deform >>>>>>>>>>>>>>>> a pipe geometry. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Dear Paul, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I tried many ways to map my straight pipe geometry but it >>>>>>>>>>>>>>>> does not seem to work properly >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I used something like >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> X = X + Z * tan ( alpha ) >>>>>>>>>>>>>>>> Y = Y + Z* tan (alpha ) >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> even that dint work. could please help me with this >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Kamal. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> On Jan 17, 2014, at 2:24 PM, >>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Thanks paul. I tried working with the diverging mesh >>>>>>>>>>>>>>>>> modification. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> z = mx + b >>>>>>>>>>>>>>>>> z = ny + c >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> x = ( z - b ) / m >>>>>>>>>>>>>>>>> y = (z - c) / n >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Do you think would work ? or is there any other way to >>>>>>>>>>>>>>>>> input that ? >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> On 17/01/2014 14:14, >>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> 1) To check for convergence, run your simulation for >>>>>>>>>>>>>>>>>> increasing polynomial orders ( lx1 in the SIZE file) and >>>>>>>>>>>>>>>>>> measure some consistent quantity (drag, TKE, etc). You >>>>>>>>>>>>>>>>>> can plot this quantity against lx1 and this should give >>>>>>>>>>>>>>>>>> you a good picture of how you are converging (without >>>>>>>>>>>>>>>>>> needing to change the physical mesh). >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> 2) If you weren't using temperature in your simulation, >>>>>>>>>>>>>>>>>> you could do put the following code snippet in your >>>>>>>>>>>>>>>>>> userchk >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>>>>> integer i, ntot >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in >>>>>>>>>>>>>>>>>> simulation (on THIS processor) >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> do i = 1,ntot >>>>>>>>>>>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + >>>>>>>>>>>>>>>>>> vz(i,1,1,1)**2) >>>>>>>>>>>>>>>>>> enddo >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> ifto = .true. >>>>>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> I've assumed here that your density is unity. This >>>>>>>>>>>>>>>>>> computed kinetic energy point-wise and stores it in the >>>>>>>>>>>>>>>>>> temperature field. The part "ifto = .true." tells Nek to >>>>>>>>>>>>>>>>>> output the temperature field whenever it outputs a field >>>>>>>>>>>>>>>>>> file. You could then view this in visit just like you >>>>>>>>>>>>>>>>>> would the velocity field. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Hope this helps! >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Josh >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, >>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> I will try that mapping, I created a straight pipe to do >>>>>>>>>>>>>>>>>> some simulations. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> 1) Is there a way to check my spectral convergence, so >>>>>>>>>>>>>>>>>> that I can do some mesh convergence study? >>>>>>>>>>>>>>>>>> 2) Is there a way to plot the kinetic energy in the >>>>>>>>>>>>>>>>>> flow ? >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Hi Kamal, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> For the geometry you describe, I would apply mesh >>>>>>>>>>>>>>>>>> morphing >>>>>>>>>>>>>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>>>>>>>>>>>>> using a subset of the mkmesh script provided in the >>>>>>>>>>>>>>>>>> expansion >>>>>>>>>>>>>>>>>> example. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>>>>>>>>>>> certain that the change in slope occurs at element >>>>>>>>>>>>>>>>>> boundaries, >>>>>>>>>>>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> _______________ >>>>>>>>>>>>>>>>>> /| | | >>>>>>>>>>>>>>>>>> / | | | >>>>>>>>>>>>>>>>>> /| | | | >>>>>>>>>>>>>>>>>> ________________/ | | | | >>>>>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> I looked at the example and it looks very helpful, >>>>>>>>>>>>>>>>>> but for >>>>>>>>>>>>>>>>>> a sudden expansion we have only two parts (i.e) the >>>>>>>>>>>>>>>>>> inlet >>>>>>>>>>>>>>>>>> pipe and the outlet pipe. Whereas in a diverging pipe we >>>>>>>>>>>>>>>>>> have three section (i.e,) The inlet pipe, Diverging >>>>>>>>>>>>>>>>>> section and the outlet pipe. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Is it possible for me to create a 2D diverging section >>>>>>>>>>>>>>>>>> using mesh modification and revolve it around the centre >>>>>>>>>>>>>>>>>> axis to get a 3d diverging pipe ? >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> or should I apply the mesh modification directly to >>>>>>>>>>>>>>>>>> the 3d >>>>>>>>>>>>>>>>>> sudden expansion pipe using usrdat2() ? >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Thanks a lot for the update. I will take a look at as >>>>>>>>>>>>>>>>>> soon >>>>>>>>>>>>>>>>>> as possible and keep you updated with it. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> On Jan 14, 2014, at 9:04 PM, >>>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> I've added an example for a step-type expansion in a >>>>>>>>>>>>>>>>>> pipe. >>>>>>>>>>>>>>>>>> New example directory >>>>>>>>>>>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> If you want a standard diffuser, I would use >>>>>>>>>>>>>>>>>> mesh-morphing, as outlined in the >>>>>>>>>>>>>>>>>> nek primer, which can be found on this page: >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> I've also automated our turbulent outflow bc >>>>>>>>>>>>>>>>>> treatment -- >>>>>>>>>>>>>>>>>> one simply provides an >>>>>>>>>>>>>>>>>> expansion factor (typically ~ 1.5) and two persistent >>>>>>>>>>>>>>>>>> arrays to turb_outflow(), which >>>>>>>>>>>>>>>>>> is now in navier5.f. This can be useful when very >>>>>>>>>>>>>>>>>> strong vortices are leaving the >>>>>>>>>>>>>>>>>> domain, which is possible for certain diffuser flow >>>>>>>>>>>>>>>>>> conditions (and others). >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>>>> ________________________________________ >>>>>>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf >>>>>>>>>>>>>>>>>> ofnek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Hi >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Can some one please help me in this because I am new >>>>>>>>>>>>>>>>>> to nek >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> 1) How can I create a .rea for a specific geometry >>>>>>>>>>>>>>>>>> say ' A >>>>>>>>>>>>>>>>>> sudden >>>>>>>>>>>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> kamal >>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> -- >>>>>>>>>>>>>>>>>> Josh Camp >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> "All that is necessary for the triumph of evil is that >>>>>>>>>>>>>>>>>> good men do nothing" -- Edmund Burke >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >> >> On Fri, 24 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >> >>> Hello Paul, >>> >>> Thanks for your reply. I am looking into the .usr file for defining >>> the set_obj (). >>> >>> 1) Could you please tell me what is 'Enter the number of levels ?' >>> in n2to3 >>> >>> is it the number of elements in Z direction ? >>> >>> 2) As you said about storing the computed vorticity in velocity >>> field to view in VisIT, I found the routine to compute the vorticity >>> but I am stuck about adding it to the velocity filed to VisIT ? >>> could you please tell me how it works or any example which stores >>> vorticity to the .fld file as a separate variable. >>> >>> >>> Thank you >>> >>> Kamal >>> >>> >>> On 22/01/2014 16:53, nek5000-users at lists.mcs.anl.gov wrote: >>>> Axial viscous stress is given by torq_calc -- that's no problem >>>> whatsoever. You get a number as a >>>> function of time. >>>> >>>> You can even get stresses on multiple subsets of the geometry >>>> (e.g., if you had multiple branches >>>> in the domain or multiple cylinders. The drag, which is a >>>> byproduct of the torque computation (which >>>> you can ignore), is given in terms of the viscous and pressure >>>> components separately and as the >>>> sum of the two. >>>> >>>> You can identify domain boundaries by checking the boundary >>>> conditions. Here, I recommend >>>> looking at the set_obj routines in several of the /example cases. >>>> >>>> >>>> ________________________________________ >>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>> Sent: Wednesday, January 22, 2014 9:37 AM >>>> To: nek5000-users at lists.mcs.anl.gov >>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>> >>>> Hello Paul >>>> >>>> I was thinking about taking the tangential velocity near to the >>>> wall so that I can figure out my length of the recirculation region. >>>> >>>> Is it possible for me to access the boundary elements of the mesh >>>> ??? so that I can take the boundary element and then obtain the >>>> velocity at that point so that I can figure out the length of my >>>> recirculation region. >>>> >>>> or take the *.fld file and read it to plot the datas I need. >>>> >>>> >>>> I also want to calculate the axial viscous force acting on the >>>> entire pipe. >>>> >>>> which is given by >>>> >>>> C_v = F^v / ( d^2 * rho * U^2 ) = double integral ( 1/Re * (du / >>>> dr) ) dtheta dz >>>> >>>> >>>> On Jan 22, 2014, at 4:07 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> Hi Kamal, >>>>> >>>>> As I thought about it some more, if you're interested in the local >>>>> wall shear stress >>>>> magnitude I'm quite certain you can get this by plotting the >>>>> magnitude of vorticity >>>>> on the surface in question. (Note that the sign of the WSS, >>>>> which in fact is a tensor >>>>> or a vector when restricted to a given surface, is lost in this >>>>> process, but that might >>>>> not be relevant for your needs.) If that works, then you can >>>>> readily compute the >>>>> vorticity using one of the routines in nek and store the result in >>>>> a velocity field, then >>>>> view that field with VisIt. Of course WSS will require >>>>> multiplication by viscosity. >>>>> >>>>> hth, >>>>> >>>>> Paul >>>>> >>>>> ________________________________________ >>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>> Sent: Tuesday, January 21, 2014 10:33 AM >>>>> To: nek5000-users at lists.mcs.anl.gov >>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>> >>>>> Hi paul, >>>>> >>>>> can I make this to be drag or shear quantities to be return to the a >>>>> separate file so that it will easy for me to plot. >>>>> >>>>> By the way it gives the integral quantity. Think for example I >>>>> need to >>>>> find the shear stress on the wall from the inlet to outlet at a >>>>> particular time = 2 . How can I do that ? >>>>> >>>>> Is there way to find the number of elements in x,y and z direction ? >>>>> >>>>> On 21/01/2014 17:32, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> Hi Kamal, >>>>>> >>>>>> Your integrated drag quantities should be written to the logfile >>>>>> (stdout), >>>>>> assuming you've set the arguments in the call to be .true. >>>>>> >>>>>> Paul >>>>>> >>>>>> On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>>> Hi Paul, >>>>>>> >>>>>>> I checked the set_obj subroutine and implemented one in my .USR >>>>>>> file. >>>>>>> The code seem to run without any errors but I don't find where >>>>>>> these >>>>>>> variables are getting stored. >>>>>>> >>>>>>> I use VisIT to visualize my output, even there was no change in it. >>>>>>> >>>>>>> do I have to define my own output file and write the variables >>>>>>> out ? >>>>>>> >>>>>>> Thanks, >>>>>>> >>>>>>> Kamal. >>>>>>> >>>>>>> >>>>>>> On 20/01/2014 21:52, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> Hi Kamal, >>>>>>>> >>>>>>>> You'll need to compute your own tke by manipulating the >>>>>>>> velocity fields. >>>>>>>> >>>>>>>> You can get running averages of the requisite quantities >>>>>>>> via calls to "avg_all" which is found in navier5.f >>>>>>>> >>>>>>>> You can compute shear stress on the wall simply by computing >>>>>>>> the drag on the wall, which can be done via a call to >>>>>>>> torque_calc(), >>>>>>>> also found in navier5.f >>>>>>>> >>>>>>>> If you cd to /examples and type: >>>>>>>> >>>>>>>> grep torq */*.usr >>>>>>>> >>>>>>>> you'll find many examples of calls to torque_calc. You simply >>>>>>>> need to prescribe the surfaces on which shear is to be integrated. >>>>>>>> >>>>>>>> I typically write a routine "set_obj" to identify such surfaces >>>>>>>> on the first call to usrchk. >>>>>>>> >>>>>>>> grep set_obj */*.usr >>>>>>>> >>>>>>>> will show similar examples. >>>>>>>> >>>>>>>> I would recommend trying this for laminar Poiseiulle flow in >>>>>>>> a very simple channel just to check that your calls are properly >>>>>>>> set. >>>>>>>> >>>>>>>> Best, >>>>>>>> >>>>>>>> Paul >>>>>>>> >>>>>>>> >>>>>>>> On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> >>>>>>>>> Hi Paul, >>>>>>>>> >>>>>>>>> Thanks and that helped. >>>>>>>>> >>>>>>>>> Where can I find the variables like Turbulent KE , shear >>>>>>>>> stress on >>>>>>>>> the wall. ? >>>>>>>>> >>>>>>>>> Do i have to activate some parameters for calculating them ? >>>>>>>>> >>>>>>>>> If I had to plot them. >>>>>>>>> >>>>>>>>> Thanks, >>>>>>>>> Kamal >>>>>>>>> >>>>>>>>> >>>>>>>>> On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov >>>>>>>>> wrote: >>>>>>>>> >>>>>>>>>> Kamal, >>>>>>>>>> >>>>>>>>>> Looks good. >>>>>>>>>> >>>>>>>>>> I'm guessing that one further refinement would be: >>>>>>>>>> >>>>>>>>>> if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) >>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>> >>>>>>>>>> which would yield >>>>>>>>>> >>>>>>>>>> scale = 1 when z=z0 >>>>>>>>>> scale = smax when z >= z1 >>>>>>>>>> >>>>>>>>>> Paul >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>> >>>>>>>>>>> Hi paul, >>>>>>>>>>> >>>>>>>>>>> The code works fine, but there should be a small change >>>>>>>>>>> thats has >>>>>>>>>>> to be done >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >>>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>>> >>>>>>>>>>> This creates a perfect diverging pipe. >>>>>>>>>>> >>>>>>>>>>> Thanks for the help paul. >>>>>>>>>>> >>>>>>>>>>> Kamal >>>>>>>>>>> >>>>>>>>>>> On Jan 20, 2014, at 12:09 AM, >>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>> >>>>>>>>>>>> Hi paul, >>>>>>>>>>>> >>>>>>>>>>>> If I am not wrong, >>>>>>>>>>>> I make a mesh with three straight pipes( inlet, divergent, >>>>>>>>>>>> outlet ) connected together via n2to3 so that I know the >>>>>>>>>>>> element >>>>>>>>>>>> connectivity places of the divergent section (z0,z1) and >>>>>>>>>>>> use the >>>>>>>>>>>> section what you gave >>>>>>>>>>>> >>>>>>>>>>>> Thank you for the code >>>>>>>>>>>> >>>>>>>>>>>> Kamal >>>>>>>>>>>> >>>>>>>>>>>> On Jan 19, 2014, at 8:45 PM, >>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>> >>>>>>>>>>>>> Kamal, >>>>>>>>>>>>> >>>>>>>>>>>>> I would do the following in usrdat2(): >>>>>>>>>>>>> >>>>>>>>>>>>> n=nx1*ny1*nz1*nelt >>>>>>>>>>>>> >>>>>>>>>>>>> do i=1,n >>>>>>>>>>>>> x=xm1(i,1,1,1) >>>>>>>>>>>>> y=ym1(i,1,1,1) >>>>>>>>>>>>> z=ym1(i,1,1,1) >>>>>>>>>>>>> scale = 1. >>>>>>>>>>>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>>>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>>>>> xm1(i,1,1,1) = scale*x >>>>>>>>>>>>> ym1(i,1,1,1) = scale*y >>>>>>>>>>>>> enddo >>>>>>>>>>>>> >>>>>>>>>>>>> Paul >>>>>>>>>>>>> >>>>>>>>>>>>> Make certain that z1 and z0 correspond to z values >>>>>>>>>>>>> that precisely coincide with element interfaces. >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>> >>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> I looked into the Peris example but It is so what same like >>>>>>>>>>>>>> the stenosis example with a Cosine deformation. >>>>>>>>>>>>>> >>>>>>>>>>>>>> In my case it is a pipe with conical divergent. I tried to >>>>>>>>>>>>>> play around the variables Xm1, Ym1 and Zm1 but the mapping >>>>>>>>>>>>>> doesn't go well. >>>>>>>>>>>>>> >>>>>>>>>>>>>> Could you please help me with this. >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I looked at the Helix and stenosis example but they are >>>>>>>>>>>>>>> using >>>>>>>>>>>>>>> cosine functions to deform >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I tried to use a tangent function but it bends the whole >>>>>>>>>>>>>>> pipe. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I dint look at peris example . >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I will take a look at it and let you know. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> On Jan 18, 2014, at 7:22 PM, >>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Have you looked at the peris example? The usr file there >>>>>>>>>>>>>>>> shows how to deform >>>>>>>>>>>>>>>> a pipe geometry. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Dear Paul, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I tried many ways to map my straight pipe geometry but it >>>>>>>>>>>>>>>> does not seem to work properly >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I used something like >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> X = X + Z * tan ( alpha ) >>>>>>>>>>>>>>>> Y = Y + Z* tan (alpha ) >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> even that dint work. could please help me with this >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Kamal. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> On Jan 17, 2014, at 2:24 PM, >>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Thanks paul. I tried working with the diverging mesh >>>>>>>>>>>>>>>>> modification. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> z = mx + b >>>>>>>>>>>>>>>>> z = ny + c >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> x = ( z - b ) / m >>>>>>>>>>>>>>>>> y = (z - c) / n >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Do you think would work ? or is there any other way to >>>>>>>>>>>>>>>>> input that ? >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> On 17/01/2014 14:14, >>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> 1) To check for convergence, run your simulation for >>>>>>>>>>>>>>>>>> increasing polynomial orders ( lx1 in the SIZE file) and >>>>>>>>>>>>>>>>>> measure some consistent quantity (drag, TKE, etc). You >>>>>>>>>>>>>>>>>> can plot this quantity against lx1 and this should give >>>>>>>>>>>>>>>>>> you a good picture of how you are converging (without >>>>>>>>>>>>>>>>>> needing to change the physical mesh). >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> 2) If you weren't using temperature in your simulation, >>>>>>>>>>>>>>>>>> you could do put the following code snippet in your >>>>>>>>>>>>>>>>>> userchk >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>>>>> integer i, ntot >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in >>>>>>>>>>>>>>>>>> simulation (on THIS processor) >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> do i = 1,ntot >>>>>>>>>>>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + >>>>>>>>>>>>>>>>>> vz(i,1,1,1)**2) >>>>>>>>>>>>>>>>>> enddo >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> ifto = .true. >>>>>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> I've assumed here that your density is unity. This >>>>>>>>>>>>>>>>>> computed kinetic energy point-wise and stores it in the >>>>>>>>>>>>>>>>>> temperature field. The part "ifto = .true." tells Nek to >>>>>>>>>>>>>>>>>> output the temperature field whenever it outputs a field >>>>>>>>>>>>>>>>>> file. You could then view this in visit just like you >>>>>>>>>>>>>>>>>> would the velocity field. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Hope this helps! >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Josh >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, >>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> I will try that mapping, I created a straight pipe to do >>>>>>>>>>>>>>>>>> some simulations. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> 1) Is there a way to check my spectral convergence, so >>>>>>>>>>>>>>>>>> that I can do some mesh convergence study? >>>>>>>>>>>>>>>>>> 2) Is there a way to plot the kinetic energy in the >>>>>>>>>>>>>>>>>> flow ? >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Hi Kamal, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> For the geometry you describe, I would apply mesh >>>>>>>>>>>>>>>>>> morphing >>>>>>>>>>>>>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>>>>>>>>>>>>> using a subset of the mkmesh script provided in the >>>>>>>>>>>>>>>>>> expansion >>>>>>>>>>>>>>>>>> example. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>>>>>>>>>>> certain that the change in slope occurs at element >>>>>>>>>>>>>>>>>> boundaries, >>>>>>>>>>>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> _______________ >>>>>>>>>>>>>>>>>> /| | | >>>>>>>>>>>>>>>>>> / | | | >>>>>>>>>>>>>>>>>> /| | | | >>>>>>>>>>>>>>>>>> ________________/ | | | | >>>>>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> I looked at the example and it looks very helpful, >>>>>>>>>>>>>>>>>> but for >>>>>>>>>>>>>>>>>> a sudden expansion we have only two parts (i.e) the >>>>>>>>>>>>>>>>>> inlet >>>>>>>>>>>>>>>>>> pipe and the outlet pipe. Whereas in a diverging pipe we >>>>>>>>>>>>>>>>>> have three section (i.e,) The inlet pipe, Diverging >>>>>>>>>>>>>>>>>> section and the outlet pipe. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Is it possible for me to create a 2D diverging section >>>>>>>>>>>>>>>>>> using mesh modification and revolve it around the centre >>>>>>>>>>>>>>>>>> axis to get a 3d diverging pipe ? >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> or should I apply the mesh modification directly to >>>>>>>>>>>>>>>>>> the 3d >>>>>>>>>>>>>>>>>> sudden expansion pipe using usrdat2() ? >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Thanks a lot for the update. I will take a look at as >>>>>>>>>>>>>>>>>> soon >>>>>>>>>>>>>>>>>> as possible and keep you updated with it. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> On Jan 14, 2014, at 9:04 PM, >>>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> I've added an example for a step-type expansion in a >>>>>>>>>>>>>>>>>> pipe. >>>>>>>>>>>>>>>>>> New example directory >>>>>>>>>>>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> If you want a standard diffuser, I would use >>>>>>>>>>>>>>>>>> mesh-morphing, as outlined in the >>>>>>>>>>>>>>>>>> nek primer, which can be found on this page: >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> I've also automated our turbulent outflow bc >>>>>>>>>>>>>>>>>> treatment -- >>>>>>>>>>>>>>>>>> one simply provides an >>>>>>>>>>>>>>>>>> expansion factor (typically ~ 1.5) and two persistent >>>>>>>>>>>>>>>>>> arrays to turb_outflow(), which >>>>>>>>>>>>>>>>>> is now in navier5.f. This can be useful when very >>>>>>>>>>>>>>>>>> strong vortices are leaving the >>>>>>>>>>>>>>>>>> domain, which is possible for certain diffuser flow >>>>>>>>>>>>>>>>>> conditions (and others). >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>>>> ________________________________________ >>>>>>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf >>>>>>>>>>>>>>>>>> ofnek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Hi >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Can some one please help me in this because I am new >>>>>>>>>>>>>>>>>> to nek >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> 1) How can I create a .rea for a specific geometry >>>>>>>>>>>>>>>>>> say ' A >>>>>>>>>>>>>>>>>> sudden >>>>>>>>>>>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> kamal >>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> -- >>>>>>>>>>>>>>>>>> Josh Camp >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> "All that is necessary for the triumph of evil is that >>>>>>>>>>>>>>>>>> good men do nothing" -- Edmund Burke >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Fri Jan 31 11:17:02 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Fri, 31 Jan 2014 11:17:02 -0600 (CST) Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , , Message-ID: Hi Kamal, For steady state, Nek supports only Stokes and conduction. There is some discussion of this on p. 16 of the manual, which you can find by following this link: http://nek5000.mcs.anl.gov/index.php/UG#Documentation Best, Paul On Fri, 31 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > Hi Neks, > > I tried to simulated steady flow by setting the logical operator IFTRAN = F > but the simulation still runs in transient mode, How do I get a steady time > independent solution so that I can use it as my Initial Condition ? > > Thank you, > Kamal > > > On 29/01/2014 16:01, nek5000-users at lists.mcs.anl.gov wrote: >> Hello Paul, >> >> Thanks for the vorticity output and it worked. >> >> >> 1) I created a set-obj() for my pipe but how can I be sure that it has >> taken the full pipe wall surface in to account ? >> I have attached the divpipe.usr file for your reference could you >> please take a look at it. >> >> 2) I even took torque_calc in to the .usr file and it gives out something >> like this >> >> 200 1.00000000000E+00 -9.76942759878E-06 -8.98721249598E-06 >> -7.82215102801E-07 1torqx >> 200 1.00000000000E+00 -6.69169235606E-06 -6.35251009840E-06 >> -3.39182257669E-07 1torqy >> 200 1.00000000000E+00 9.50518561890E-10 1.50349344990E-13 >> 9.50368212545E-10 1torqz >> >> if I am not wrong are these the value of surface integral of viscous force >> in three components of velocity along three directions taken in the >> set_obj() ? >> >> because I would like to calculate this >> >> C_v = F^v / ( d^2 * rho * U^2 ) = double integral ( 1/Re * (du / dr) ) >> dtheta dz >> >> >> Thank you, >> >> Kamal. >> >> >> On 24/01/2014 13:02, nek5000-users at lists.mcs.anl.gov wrote: >>> >>> >>> >>> Kamal, >>> >>> 1) yes >>> >>> 2) standard approach to seeing vorticity would be something >>> like the following in userchk >>> >>> parameter (lt=lx1*ly1*lz1*lelt) >>> common /myjunk/ vort(lt,3),w1(lt),w2(lt) >>> logical ifxyt >>> integer ivout ! flag to turn geometry on/off for VisIt >>> save ivout >>> data ivout /0/ >>> >>> >>> if (mod(istep,iostep).eq.0) then >>> call comp_vort3(vort,w1,w2,vx,vy,vz) >>> >>> ifxyt = ifxyo ! put geometry into first vrt file >>> ifxyo = .false. >>> if (ivout.eq.0) ifxyo = .true. >>> ivout = 1 >>> >>> call outpost(vort(1,1),vort(1,2),vort(1,3),pr,t,'vrt') >>> >>> ifxyo = ifxyt ! restore ifxyo flag to original state >>> >>> endif >>> >>> >>> If your session name is blah, this piece of code will put >>> vorticity into a sequence of files vrtblah0.f0000n >>> >>> You can instead ignore the vrt prefix and the part about the >>> geometry with a simpler code >>> >>> parameter (lt=lx1*ly1*lz1*lelt) >>> common /myjunk/ vort(lt,3),w1(lt),w2(lt) >>> >>> if (mod(istep,iostep).eq.0) then >>> call comp_vort3(vort,w1,w2,vx,vy,vz) >>> call outpost(vort(1,1),vort(1,2),vort(1,3),pr,t,'vrt') >>> endif >>> >>> I usually go for this latter approach, but the choice is >>> totally up to you. >>> >>> Paul >>> >>> >>> >>> >>> >>> On Fri, 24 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>> >>>> Hello Paul, >>>> >>>> Thanks for your reply. I am looking into the .usr file for defining the >>>> set_obj (). >>>> >>>> 1) Could you please tell me what is 'Enter the number of levels ?' in >>>> n2to3 >>>> >>>> is it the number of elements in Z direction ? >>>> >>>> 2) As you said about storing the computed vorticity in velocity field to >>>> view in VisIT, I found the routine to compute the vorticity but I am >>>> stuck about adding it to the velocity filed to VisIT ? could you please >>>> tell me how it works or any example which stores vorticity to the .fld >>>> file as a separate variable. >>>> >>>> >>>> Thank you >>>> >>>> Kamal >>>> >>>> >>>> On 22/01/2014 16:53, nek5000-users at lists.mcs.anl.gov wrote: >>>>> Axial viscous stress is given by torq_calc -- that's no problem >>>>> whatsoever. You get a number as a >>>>> function of time. >>>>> >>>>> You can even get stresses on multiple subsets of the geometry (e.g., if >>>>> you had multiple branches >>>>> in the domain or multiple cylinders. The drag, which is a byproduct of >>>>> the torque computation (which >>>>> you can ignore), is given in terms of the viscous and pressure >>>>> components separately and as the >>>>> sum of the two. >>>>> >>>>> You can identify domain boundaries by checking the boundary conditions. >>>>> Here, I recommend >>>>> looking at the set_obj routines in several of the /example cases. >>>>> >>>>> >>>>> ________________________________________ >>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>> Sent: Wednesday, January 22, 2014 9:37 AM >>>>> To: nek5000-users at lists.mcs.anl.gov >>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>> >>>>> Hello Paul >>>>> >>>>> I was thinking about taking the tangential velocity near to the wall so >>>>> that I can figure out my length of the recirculation region. >>>>> >>>>> Is it possible for me to access the boundary elements of the mesh ??? so >>>>> that I can take the boundary element and then obtain the velocity at >>>>> that point so that I can figure out the length of my recirculation >>>>> region. >>>>> >>>>> or take the *.fld file and read it to plot the datas I need. >>>>> >>>>> >>>>> I also want to calculate the axial viscous force acting on the entire >>>>> pipe. >>>>> >>>>> which is given by >>>>> >>>>> C_v = F^v / ( d^2 * rho * U^2 ) = double integral ( 1/Re * (du / dr) >>>>> ) dtheta dz >>>>> >>>>> >>>>> On Jan 22, 2014, at 4:07 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>>> Hi Kamal, >>>>>> >>>>>> As I thought about it some more, if you're interested in the local wall >>>>>> shear stress >>>>>> magnitude I'm quite certain you can get this by plotting the magnitude >>>>>> of vorticity >>>>>> on the surface in question. (Note that the sign of the WSS, which in >>>>>> fact is a tensor >>>>>> or a vector when restricted to a given surface, is lost in this >>>>>> process, but that might >>>>>> not be relevant for your needs.) If that works, then you can readily >>>>>> compute the >>>>>> vorticity using one of the routines in nek and store the result in a >>>>>> velocity field, then >>>>>> view that field with VisIt. Of course WSS will require multiplication >>>>>> by viscosity. >>>>>> >>>>>> hth, >>>>>> >>>>>> Paul >>>>>> >>>>>> ________________________________________ >>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>> Sent: Tuesday, January 21, 2014 10:33 AM >>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>> >>>>>> Hi paul, >>>>>> >>>>>> can I make this to be drag or shear quantities to be return to the a >>>>>> separate file so that it will easy for me to plot. >>>>>> >>>>>> By the way it gives the integral quantity. Think for example I need to >>>>>> find the shear stress on the wall from the inlet to outlet at a >>>>>> particular time = 2 . How can I do that ? >>>>>> >>>>>> Is there way to find the number of elements in x,y and z direction ? >>>>>> >>>>>> On 21/01/2014 17:32, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> Hi Kamal, >>>>>>> >>>>>>> Your integrated drag quantities should be written to the logfile >>>>>>> (stdout), >>>>>>> assuming you've set the arguments in the call to be .true. >>>>>>> >>>>>>> Paul >>>>>>> >>>>>>> On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>>> Hi Paul, >>>>>>>> >>>>>>>> I checked the set_obj subroutine and implemented one in my .USR file. >>>>>>>> The code seem to run without any errors but I don't find where these >>>>>>>> variables are getting stored. >>>>>>>> >>>>>>>> I use VisIT to visualize my output, even there was no change in it. >>>>>>>> >>>>>>>> do I have to define my own output file and write the variables out ? >>>>>>>> >>>>>>>> Thanks, >>>>>>>> >>>>>>>> Kamal. >>>>>>>> >>>>>>>> >>>>>>>> On 20/01/2014 21:52, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>> Hi Kamal, >>>>>>>>> >>>>>>>>> You'll need to compute your own tke by manipulating the >>>>>>>>> velocity fields. >>>>>>>>> >>>>>>>>> You can get running averages of the requisite quantities >>>>>>>>> via calls to "avg_all" which is found in navier5.f >>>>>>>>> >>>>>>>>> You can compute shear stress on the wall simply by computing >>>>>>>>> the drag on the wall, which can be done via a call to torque_calc(), >>>>>>>>> also found in navier5.f >>>>>>>>> >>>>>>>>> If you cd to /examples and type: >>>>>>>>> >>>>>>>>> grep torq */*.usr >>>>>>>>> >>>>>>>>> you'll find many examples of calls to torque_calc. You simply >>>>>>>>> need to prescribe the surfaces on which shear is to be integrated. >>>>>>>>> >>>>>>>>> I typically write a routine "set_obj" to identify such surfaces >>>>>>>>> on the first call to usrchk. >>>>>>>>> >>>>>>>>> grep set_obj */*.usr >>>>>>>>> >>>>>>>>> will show similar examples. >>>>>>>>> >>>>>>>>> I would recommend trying this for laminar Poiseiulle flow in >>>>>>>>> a very simple channel just to check that your calls are properly >>>>>>>>> set. >>>>>>>>> >>>>>>>>> Best, >>>>>>>>> >>>>>>>>> Paul >>>>>>>>> >>>>>>>>> >>>>>>>>> On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>> >>>>>>>>>> Hi Paul, >>>>>>>>>> >>>>>>>>>> Thanks and that helped. >>>>>>>>>> >>>>>>>>>> Where can I find the variables like Turbulent KE , shear stress on >>>>>>>>>> the wall. ? >>>>>>>>>> >>>>>>>>>> Do i have to activate some parameters for calculating them ? >>>>>>>>>> >>>>>>>>>> If I had to plot them. >>>>>>>>>> >>>>>>>>>> Thanks, >>>>>>>>>> Kamal >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>> >>>>>>>>>>> Kamal, >>>>>>>>>>> >>>>>>>>>>> Looks good. >>>>>>>>>>> >>>>>>>>>>> I'm guessing that one further refinement would be: >>>>>>>>>>> >>>>>>>>>>> if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) >>>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>>> >>>>>>>>>>> which would yield >>>>>>>>>>> >>>>>>>>>>> scale = 1 when z=z0 >>>>>>>>>>> scale = smax when z >= z1 >>>>>>>>>>> >>>>>>>>>>> Paul >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>> >>>>>>>>>>>> Hi paul, >>>>>>>>>>>> >>>>>>>>>>>> The code works fine, but there should be a small change thats has >>>>>>>>>>>> to be done >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >>>>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>>>> >>>>>>>>>>>> This creates a perfect diverging pipe. >>>>>>>>>>>> >>>>>>>>>>>> Thanks for the help paul. >>>>>>>>>>>> >>>>>>>>>>>> Kamal >>>>>>>>>>>> >>>>>>>>>>>> On Jan 20, 2014, at 12:09 AM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> wrote: >>>>>>>>>>>> >>>>>>>>>>>>> Hi paul, >>>>>>>>>>>>> >>>>>>>>>>>>> If I am not wrong, >>>>>>>>>>>>> I make a mesh with three straight pipes( inlet, divergent, >>>>>>>>>>>>> outlet ) connected together via n2to3 so that I know the element >>>>>>>>>>>>> connectivity places of the divergent section (z0,z1) and use the >>>>>>>>>>>>> section what you gave >>>>>>>>>>>>> >>>>>>>>>>>>> Thank you for the code >>>>>>>>>>>>> >>>>>>>>>>>>> Kamal >>>>>>>>>>>>> >>>>>>>>>>>>> On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> wrote: >>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>> >>>>>>>>>>>>>> I would do the following in usrdat2(): >>>>>>>>>>>>>> >>>>>>>>>>>>>> n=nx1*ny1*nz1*nelt >>>>>>>>>>>>>> >>>>>>>>>>>>>> do i=1,n >>>>>>>>>>>>>> x=xm1(i,1,1,1) >>>>>>>>>>>>>> y=ym1(i,1,1,1) >>>>>>>>>>>>>> z=ym1(i,1,1,1) >>>>>>>>>>>>>> scale = 1. >>>>>>>>>>>>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>>>>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>>>>>> xm1(i,1,1,1) = scale*x >>>>>>>>>>>>>> ym1(i,1,1,1) = scale*y >>>>>>>>>>>>>> enddo >>>>>>>>>>>>>> >>>>>>>>>>>>>> Paul >>>>>>>>>>>>>> >>>>>>>>>>>>>> Make certain that z1 and z0 correspond to z values >>>>>>>>>>>>>> that precisely coincide with element interfaces. >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I looked into the Peris example but It is so what same like >>>>>>>>>>>>>>> the stenosis example with a Cosine deformation. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> In my case it is a pipe with conical divergent. I tried to >>>>>>>>>>>>>>> play around the variables Xm1, Ym1 and Zm1 but the mapping >>>>>>>>>>>>>>> doesn't go well. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Could you please help me with this. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I looked at the Helix and stenosis example but they are using >>>>>>>>>>>>>>>> cosine functions to deform >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I tried to use a tangent function but it bends the whole >>>>>>>>>>>>>>>> pipe. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I dint look at peris example . >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I will take a look at it and let you know. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Have you looked at the peris example? The usr file there >>>>>>>>>>>>>>>>> shows how to deform >>>>>>>>>>>>>>>>> a pipe geometry. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Dear Paul, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I tried many ways to map my straight pipe geometry but it >>>>>>>>>>>>>>>>> does not seem to work properly >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I used something like >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> X = X + Z * tan ( alpha ) >>>>>>>>>>>>>>>>> Y = Y + Z* tan (alpha ) >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> even that dint work. could please help me with this >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Kamal. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Thanks paul. I tried working with the diverging mesh >>>>>>>>>>>>>>>>>> modification. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> z = mx + b >>>>>>>>>>>>>>>>>> z = ny + c >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> x = ( z - b ) / m >>>>>>>>>>>>>>>>>> y = (z - c) / n >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Do you think would work ? or is there any other way to >>>>>>>>>>>>>>>>>> input that ? >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> 1) To check for convergence, run your simulation for >>>>>>>>>>>>>>>>>>> increasing polynomial orders ( lx1 in the SIZE file) and >>>>>>>>>>>>>>>>>>> measure some consistent quantity (drag, TKE, etc). You >>>>>>>>>>>>>>>>>>> can plot this quantity against lx1 and this should give >>>>>>>>>>>>>>>>>>> you a good picture of how you are converging (without >>>>>>>>>>>>>>>>>>> needing to change the physical mesh). >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> 2) If you weren't using temperature in your simulation, >>>>>>>>>>>>>>>>>>> you could do put the following code snippet in your >>>>>>>>>>>>>>>>>>> userchk >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>>>>>> integer i, ntot >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in >>>>>>>>>>>>>>>>>>> simulation (on THIS processor) >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> do i = 1,ntot >>>>>>>>>>>>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + >>>>>>>>>>>>>>>>>>> vz(i,1,1,1)**2) >>>>>>>>>>>>>>>>>>> enddo >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> ifto = .true. >>>>>>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> I've assumed here that your density is unity. This >>>>>>>>>>>>>>>>>>> computed kinetic energy point-wise and stores it in the >>>>>>>>>>>>>>>>>>> temperature field. The part "ifto = .true." tells Nek to >>>>>>>>>>>>>>>>>>> output the temperature field whenever it outputs a field >>>>>>>>>>>>>>>>>>> file. You could then view this in visit just like you >>>>>>>>>>>>>>>>>>> would the velocity field. >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Hope this helps! >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Josh >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, >>>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> I will try that mapping, I created a straight pipe to do >>>>>>>>>>>>>>>>>>> some simulations. >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> 1) Is there a way to check my spectral convergence, so >>>>>>>>>>>>>>>>>>> that I can do some mesh convergence study? >>>>>>>>>>>>>>>>>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Hi Kamal, >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> For the geometry you describe, I would apply mesh morphing >>>>>>>>>>>>>>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>>>>>>>>>>>>>> using a subset of the mkmesh script provided in the >>>>>>>>>>>>>>>>>>> expansion >>>>>>>>>>>>>>>>>>> example. >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>>>>>>>>>>>> certain that the change in slope occurs at element >>>>>>>>>>>>>>>>>>> boundaries, >>>>>>>>>>>>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> _______________ >>>>>>>>>>>>>>>>>>> /| | | >>>>>>>>>>>>>>>>>>> / | | | >>>>>>>>>>>>>>>>>>> /| | | | >>>>>>>>>>>>>>>>>>> ________________/ | | | | >>>>>>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> I looked at the example and it looks very helpful, but for >>>>>>>>>>>>>>>>>>> a sudden expansion we have only two parts (i.e) the inlet >>>>>>>>>>>>>>>>>>> pipe and the outlet pipe. Whereas in a diverging pipe we >>>>>>>>>>>>>>>>>>> have three section (i.e,) The inlet pipe, Diverging >>>>>>>>>>>>>>>>>>> section and the outlet pipe. >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Is it possible for me to create a 2D diverging section >>>>>>>>>>>>>>>>>>> using mesh modification and revolve it around the centre >>>>>>>>>>>>>>>>>>> axis to get a 3d diverging pipe ? >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> or should I apply the mesh modification directly to the 3d >>>>>>>>>>>>>>>>>>> sudden expansion pipe using usrdat2() ? >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Thanks a lot for the update. I will take a look at as soon >>>>>>>>>>>>>>>>>>> as possible and keep you updated with it. >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> On Jan 14, 2014, at 9:04 PM, >>>>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> I've added an example for a step-type expansion in a pipe. >>>>>>>>>>>>>>>>>>> New example directory >>>>>>>>>>>>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> If you want a standard diffuser, I would use >>>>>>>>>>>>>>>>>>> mesh-morphing, as outlined in the >>>>>>>>>>>>>>>>>>> nek primer, which can be found on this page: >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> I've also automated our turbulent outflow bc treatment -- >>>>>>>>>>>>>>>>>>> one simply provides an >>>>>>>>>>>>>>>>>>> expansion factor (typically ~ 1.5) and two persistent >>>>>>>>>>>>>>>>>>> arrays to turb_outflow(), which >>>>>>>>>>>>>>>>>>> is now in navier5.f. This can be useful when very >>>>>>>>>>>>>>>>>>> strong vortices are leaving the >>>>>>>>>>>>>>>>>>> domain, which is possible for certain diffuser flow >>>>>>>>>>>>>>>>>>> conditions (and others). >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>>>>> ________________________________________ >>>>>>>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf >>>>>>>>>>>>>>>>>>> ofnek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Hi >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Can some one please help me in this because I am new to >>>>>>>>>>>>>>>>>>> nek >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> 1) How can I create a .rea for a specific geometry say ' A >>>>>>>>>>>>>>>>>>> sudden >>>>>>>>>>>>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> kamal >>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> -- >>>>>>>>>>>>>>>>>>> Josh Camp >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> "All that is necessary for the triumph of evil is that >>>>>>>>>>>>>>>>>>> good men do nothing" -- Edmund Burke >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>> >>> On Fri, 24 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>> >>>> Hello Paul, >>>> >>>> Thanks for your reply. I am looking into the .usr file for defining the >>>> set_obj (). >>>> >>>> 1) Could you please tell me what is 'Enter the number of levels ?' in >>>> n2to3 >>>> >>>> is it the number of elements in Z direction ? >>>> >>>> 2) As you said about storing the computed vorticity in velocity field to >>>> view in VisIT, I found the routine to compute the vorticity but I am >>>> stuck about adding it to the velocity filed to VisIT ? could you please >>>> tell me how it works or any example which stores vorticity to the .fld >>>> file as a separate variable. >>>> >>>> >>>> Thank you >>>> >>>> Kamal >>>> >>>> >>>> On 22/01/2014 16:53, nek5000-users at lists.mcs.anl.gov wrote: >>>>> Axial viscous stress is given by torq_calc -- that's no problem >>>>> whatsoever. You get a number as a >>>>> function of time. >>>>> >>>>> You can even get stresses on multiple subsets of the geometry (e.g., if >>>>> you had multiple branches >>>>> in the domain or multiple cylinders. The drag, which is a byproduct of >>>>> the torque computation (which >>>>> you can ignore), is given in terms of the viscous and pressure >>>>> components separately and as the >>>>> sum of the two. >>>>> >>>>> You can identify domain boundaries by checking the boundary conditions. >>>>> Here, I recommend >>>>> looking at the set_obj routines in several of the /example cases. >>>>> >>>>> >>>>> ________________________________________ >>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>> Sent: Wednesday, January 22, 2014 9:37 AM >>>>> To: nek5000-users at lists.mcs.anl.gov >>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>> >>>>> Hello Paul >>>>> >>>>> I was thinking about taking the tangential velocity near to the wall so >>>>> that I can figure out my length of the recirculation region. >>>>> >>>>> Is it possible for me to access the boundary elements of the mesh ??? so >>>>> that I can take the boundary element and then obtain the velocity at >>>>> that point so that I can figure out the length of my recirculation >>>>> region. >>>>> >>>>> or take the *.fld file and read it to plot the datas I need. >>>>> >>>>> >>>>> I also want to calculate the axial viscous force acting on the entire >>>>> pipe. >>>>> >>>>> which is given by >>>>> >>>>> C_v = F^v / ( d^2 * rho * U^2 ) = double integral ( 1/Re * (du / dr) >>>>> ) dtheta dz >>>>> >>>>> >>>>> On Jan 22, 2014, at 4:07 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>> >>>>>> Hi Kamal, >>>>>> >>>>>> As I thought about it some more, if you're interested in the local wall >>>>>> shear stress >>>>>> magnitude I'm quite certain you can get this by plotting the magnitude >>>>>> of vorticity >>>>>> on the surface in question. (Note that the sign of the WSS, which in >>>>>> fact is a tensor >>>>>> or a vector when restricted to a given surface, is lost in this >>>>>> process, but that might >>>>>> not be relevant for your needs.) If that works, then you can readily >>>>>> compute the >>>>>> vorticity using one of the routines in nek and store the result in a >>>>>> velocity field, then >>>>>> view that field with VisIt. Of course WSS will require multiplication >>>>>> by viscosity. >>>>>> >>>>>> hth, >>>>>> >>>>>> Paul >>>>>> >>>>>> ________________________________________ >>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>> Sent: Tuesday, January 21, 2014 10:33 AM >>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>> >>>>>> Hi paul, >>>>>> >>>>>> can I make this to be drag or shear quantities to be return to the a >>>>>> separate file so that it will easy for me to plot. >>>>>> >>>>>> By the way it gives the integral quantity. Think for example I need to >>>>>> find the shear stress on the wall from the inlet to outlet at a >>>>>> particular time = 2 . How can I do that ? >>>>>> >>>>>> Is there way to find the number of elements in x,y and z direction ? >>>>>> >>>>>> On 21/01/2014 17:32, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> Hi Kamal, >>>>>>> >>>>>>> Your integrated drag quantities should be written to the logfile >>>>>>> (stdout), >>>>>>> assuming you've set the arguments in the call to be .true. >>>>>>> >>>>>>> Paul >>>>>>> >>>>>>> On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>> >>>>>>>> Hi Paul, >>>>>>>> >>>>>>>> I checked the set_obj subroutine and implemented one in my .USR file. >>>>>>>> The code seem to run without any errors but I don't find where these >>>>>>>> variables are getting stored. >>>>>>>> >>>>>>>> I use VisIT to visualize my output, even there was no change in it. >>>>>>>> >>>>>>>> do I have to define my own output file and write the variables out ? >>>>>>>> >>>>>>>> Thanks, >>>>>>>> >>>>>>>> Kamal. >>>>>>>> >>>>>>>> >>>>>>>> On 20/01/2014 21:52, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>> Hi Kamal, >>>>>>>>> >>>>>>>>> You'll need to compute your own tke by manipulating the >>>>>>>>> velocity fields. >>>>>>>>> >>>>>>>>> You can get running averages of the requisite quantities >>>>>>>>> via calls to "avg_all" which is found in navier5.f >>>>>>>>> >>>>>>>>> You can compute shear stress on the wall simply by computing >>>>>>>>> the drag on the wall, which can be done via a call to torque_calc(), >>>>>>>>> also found in navier5.f >>>>>>>>> >>>>>>>>> If you cd to /examples and type: >>>>>>>>> >>>>>>>>> grep torq */*.usr >>>>>>>>> >>>>>>>>> you'll find many examples of calls to torque_calc. You simply >>>>>>>>> need to prescribe the surfaces on which shear is to be integrated. >>>>>>>>> >>>>>>>>> I typically write a routine "set_obj" to identify such surfaces >>>>>>>>> on the first call to usrchk. >>>>>>>>> >>>>>>>>> grep set_obj */*.usr >>>>>>>>> >>>>>>>>> will show similar examples. >>>>>>>>> >>>>>>>>> I would recommend trying this for laminar Poiseiulle flow in >>>>>>>>> a very simple channel just to check that your calls are properly >>>>>>>>> set. >>>>>>>>> >>>>>>>>> Best, >>>>>>>>> >>>>>>>>> Paul >>>>>>>>> >>>>>>>>> >>>>>>>>> On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>> >>>>>>>>>> Hi Paul, >>>>>>>>>> >>>>>>>>>> Thanks and that helped. >>>>>>>>>> >>>>>>>>>> Where can I find the variables like Turbulent KE , shear stress on >>>>>>>>>> the wall. ? >>>>>>>>>> >>>>>>>>>> Do i have to activate some parameters for calculating them ? >>>>>>>>>> >>>>>>>>>> If I had to plot them. >>>>>>>>>> >>>>>>>>>> Thanks, >>>>>>>>>> Kamal >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>> >>>>>>>>>>> Kamal, >>>>>>>>>>> >>>>>>>>>>> Looks good. >>>>>>>>>>> >>>>>>>>>>> I'm guessing that one further refinement would be: >>>>>>>>>>> >>>>>>>>>>> if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) >>>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>>> >>>>>>>>>>> which would yield >>>>>>>>>>> >>>>>>>>>>> scale = 1 when z=z0 >>>>>>>>>>> scale = smax when z >= z1 >>>>>>>>>>> >>>>>>>>>>> Paul >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>> >>>>>>>>>>>> Hi paul, >>>>>>>>>>>> >>>>>>>>>>>> The code works fine, but there should be a small change thats has >>>>>>>>>>>> to be done >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >>>>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>>>> >>>>>>>>>>>> This creates a perfect diverging pipe. >>>>>>>>>>>> >>>>>>>>>>>> Thanks for the help paul. >>>>>>>>>>>> >>>>>>>>>>>> Kamal >>>>>>>>>>>> >>>>>>>>>>>> On Jan 20, 2014, at 12:09 AM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> wrote: >>>>>>>>>>>> >>>>>>>>>>>>> Hi paul, >>>>>>>>>>>>> >>>>>>>>>>>>> If I am not wrong, >>>>>>>>>>>>> I make a mesh with three straight pipes( inlet, divergent, >>>>>>>>>>>>> outlet ) connected together via n2to3 so that I know the element >>>>>>>>>>>>> connectivity places of the divergent section (z0,z1) and use the >>>>>>>>>>>>> section what you gave >>>>>>>>>>>>> >>>>>>>>>>>>> Thank you for the code >>>>>>>>>>>>> >>>>>>>>>>>>> Kamal >>>>>>>>>>>>> >>>>>>>>>>>>> On Jan 19, 2014, at 8:45 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> wrote: >>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>> >>>>>>>>>>>>>> I would do the following in usrdat2(): >>>>>>>>>>>>>> >>>>>>>>>>>>>> n=nx1*ny1*nz1*nelt >>>>>>>>>>>>>> >>>>>>>>>>>>>> do i=1,n >>>>>>>>>>>>>> x=xm1(i,1,1,1) >>>>>>>>>>>>>> y=ym1(i,1,1,1) >>>>>>>>>>>>>> z=ym1(i,1,1,1) >>>>>>>>>>>>>> scale = 1. >>>>>>>>>>>>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>>>>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>>>>>> xm1(i,1,1,1) = scale*x >>>>>>>>>>>>>> ym1(i,1,1,1) = scale*y >>>>>>>>>>>>>> enddo >>>>>>>>>>>>>> >>>>>>>>>>>>>> Paul >>>>>>>>>>>>>> >>>>>>>>>>>>>> Make certain that z1 and z0 correspond to z values >>>>>>>>>>>>>> that precisely coincide with element interfaces. >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I looked into the Peris example but It is so what same like >>>>>>>>>>>>>>> the stenosis example with a Cosine deformation. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> In my case it is a pipe with conical divergent. I tried to >>>>>>>>>>>>>>> play around the variables Xm1, Ym1 and Zm1 but the mapping >>>>>>>>>>>>>>> doesn't go well. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Could you please help me with this. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> On Jan 18, 2014, at 7:26 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I looked at the Helix and stenosis example but they are using >>>>>>>>>>>>>>>> cosine functions to deform >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I tried to use a tangent function but it bends the whole >>>>>>>>>>>>>>>> pipe. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I dint look at peris example . >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I will take a look at it and let you know. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> On Jan 18, 2014, at 7:22 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Have you looked at the peris example? The usr file there >>>>>>>>>>>>>>>>> shows how to deform >>>>>>>>>>>>>>>>> a pipe geometry. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Dear Paul, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I tried many ways to map my straight pipe geometry but it >>>>>>>>>>>>>>>>> does not seem to work properly >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I used something like >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> X = X + Z * tan ( alpha ) >>>>>>>>>>>>>>>>> Y = Y + Z* tan (alpha ) >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> even that dint work. could please help me with this >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Kamal. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> On Jan 17, 2014, at 2:24 PM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Thanks paul. I tried working with the diverging mesh >>>>>>>>>>>>>>>>>> modification. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> z = mx + b >>>>>>>>>>>>>>>>>> z = ny + c >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> x = ( z - b ) / m >>>>>>>>>>>>>>>>>> y = (z - c) / n >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Do you think would work ? or is there any other way to >>>>>>>>>>>>>>>>>> input that ? >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> On 17/01/2014 14:14, nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> 1) To check for convergence, run your simulation for >>>>>>>>>>>>>>>>>>> increasing polynomial orders ( lx1 in the SIZE file) and >>>>>>>>>>>>>>>>>>> measure some consistent quantity (drag, TKE, etc). You >>>>>>>>>>>>>>>>>>> can plot this quantity against lx1 and this should give >>>>>>>>>>>>>>>>>>> you a good picture of how you are converging (without >>>>>>>>>>>>>>>>>>> needing to change the physical mesh). >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> 2) If you weren't using temperature in your simulation, >>>>>>>>>>>>>>>>>>> you could do put the following code snippet in your >>>>>>>>>>>>>>>>>>> userchk >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>>>>>> integer i, ntot >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in >>>>>>>>>>>>>>>>>>> simulation (on THIS processor) >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> do i = 1,ntot >>>>>>>>>>>>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + >>>>>>>>>>>>>>>>>>> vz(i,1,1,1)**2) >>>>>>>>>>>>>>>>>>> enddo >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> ifto = .true. >>>>>>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> I've assumed here that your density is unity. This >>>>>>>>>>>>>>>>>>> computed kinetic energy point-wise and stores it in the >>>>>>>>>>>>>>>>>>> temperature field. The part "ifto = .true." tells Nek to >>>>>>>>>>>>>>>>>>> output the temperature field whenever it outputs a field >>>>>>>>>>>>>>>>>>> file. You could then view this in visit just like you >>>>>>>>>>>>>>>>>>> would the velocity field. >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Hope this helps! >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Josh >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, >>>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> I will try that mapping, I created a straight pipe to do >>>>>>>>>>>>>>>>>>> some simulations. >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> 1) Is there a way to check my spectral convergence, so >>>>>>>>>>>>>>>>>>> that I can do some mesh convergence study? >>>>>>>>>>>>>>>>>>> 2) Is there a way to plot the kinetic energy in the flow ? >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> On 15/01/2014 12:14, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Hi Kamal, >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> For the geometry you describe, I would apply mesh morphing >>>>>>>>>>>>>>>>>>> to a standard straight pipe. You can create such a pipe >>>>>>>>>>>>>>>>>>> using a subset of the mkmesh script provided in the >>>>>>>>>>>>>>>>>>> expansion >>>>>>>>>>>>>>>>>>> example. >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>>>>>>>>>>>> certain that the change in slope occurs at element >>>>>>>>>>>>>>>>>>> boundaries, >>>>>>>>>>>>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> _______________ >>>>>>>>>>>>>>>>>>> /| | | >>>>>>>>>>>>>>>>>>> / | | | >>>>>>>>>>>>>>>>>>> /| | | | >>>>>>>>>>>>>>>>>>> ________________/ | | | | >>>>>>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> On Wed, 15 Jan 2014, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> I looked at the example and it looks very helpful, but for >>>>>>>>>>>>>>>>>>> a sudden expansion we have only two parts (i.e) the inlet >>>>>>>>>>>>>>>>>>> pipe and the outlet pipe. Whereas in a diverging pipe we >>>>>>>>>>>>>>>>>>> have three section (i.e,) The inlet pipe, Diverging >>>>>>>>>>>>>>>>>>> section and the outlet pipe. >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Is it possible for me to create a 2D diverging section >>>>>>>>>>>>>>>>>>> using mesh modification and revolve it around the centre >>>>>>>>>>>>>>>>>>> axis to get a 3d diverging pipe ? >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> or should I apply the mesh modification directly to the 3d >>>>>>>>>>>>>>>>>>> sudden expansion pipe using usrdat2() ? >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> On 14/01/2014 21:09, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Thanks a lot for the update. I will take a look at as soon >>>>>>>>>>>>>>>>>>> as possible and keep you updated with it. >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> On Jan 14, 2014, at 9:04 PM, >>>>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> I've added an example for a step-type expansion in a pipe. >>>>>>>>>>>>>>>>>>> New example directory >>>>>>>>>>>>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> If you want a standard diffuser, I would use >>>>>>>>>>>>>>>>>>> mesh-morphing, as outlined in the >>>>>>>>>>>>>>>>>>> nek primer, which can be found on this page: >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> I've also automated our turbulent outflow bc treatment -- >>>>>>>>>>>>>>>>>>> one simply provides an >>>>>>>>>>>>>>>>>>> expansion factor (typically ~ 1.5) and two persistent >>>>>>>>>>>>>>>>>>> arrays to turb_outflow(), which >>>>>>>>>>>>>>>>>>> is now in navier5.f. This can be useful when very >>>>>>>>>>>>>>>>>>> strong vortices are leaving the >>>>>>>>>>>>>>>>>>> domain, which is possible for certain diffuser flow >>>>>>>>>>>>>>>>>>> conditions (and others). >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>>>>> ________________________________________ >>>>>>>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf >>>>>>>>>>>>>>>>>>> ofnek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Hi >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Can some one please help me in this because I am new to >>>>>>>>>>>>>>>>>>> nek >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> 1) How can I create a .rea for a specific geometry say ' A >>>>>>>>>>>>>>>>>>> sudden >>>>>>>>>>>>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> kamal >>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> -- >>>>>>>>>>>>>>>>>>> Josh Camp >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> "All that is necessary for the triumph of evil is that >>>>>>>>>>>>>>>>>>> good men do nothing" -- Edmund Burke >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>> >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>> >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>> >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> >> >> _______________________________________________ >> Nek5000-users mailing list >> Nek5000-users at lists.mcs.anl.gov >> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > From nek5000-users at lists.mcs.anl.gov Fri Jan 31 11:15:53 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Fri, 31 Jan 2014 18:15:53 +0100 Subject: [Nek5000-users] Pipe with expansion In-Reply-To: References: , , Message-ID: Hi Paul, Thanks a lot for the reply. I am stuck with Set_obj() part of the simulation could you please take a look at it. Thank you, Kamal On 31/01/2014 18:17, nek5000-users at lists.mcs.anl.gov wrote: > > Hi Kamal, > > For steady state, Nek supports only Stokes and conduction. > > There is some discussion of this on p. 16 of the manual, which > you can find by following this link: > > http://nek5000.mcs.anl.gov/index.php/UG#Documentation > > Best, > > Paul > > > On Fri, 31 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: > >> Hi Neks, >> >> I tried to simulated steady flow by setting the logical operator >> IFTRAN = F but the simulation still runs in transient mode, How do I >> get a steady time independent solution so that I can use it as my >> Initial Condition ? >> >> Thank you, >> Kamal >> >> >> On 29/01/2014 16:01, nek5000-users at lists.mcs.anl.gov wrote: >>> Hello Paul, >>> >>> Thanks for the vorticity output and it worked. >>> >>> >>> 1) I created a set-obj() for my pipe but how can I be sure that it >>> has taken the full pipe wall surface in to account ? >>> I have attached the divpipe.usr file for your reference could >>> you please take a look at it. >>> >>> 2) I even took torque_calc in to the .usr file and it gives out >>> something like this >>> >>> 200 1.00000000000E+00 -9.76942759878E-06 -8.98721249598E-06 >>> -7.82215102801E-07 1torqx >>> 200 1.00000000000E+00 -6.69169235606E-06 -6.35251009840E-06 >>> -3.39182257669E-07 1torqy >>> 200 1.00000000000E+00 9.50518561890E-10 1.50349344990E-13 >>> 9.50368212545E-10 1torqz >>> >>> if I am not wrong are these the value of surface integral of viscous >>> force in three components of velocity along three directions taken >>> in the set_obj() ? >>> >>> because I would like to calculate this >>> >>> C_v = F^v / ( d^2 * rho * U^2 ) = double integral ( 1/Re * (du / >>> dr) ) dtheta dz >>> >>> >>> Thank you, >>> >>> Kamal. >>> >>> >>> On 24/01/2014 13:02, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>> >>>> >>>> Kamal, >>>> >>>> 1) yes >>>> >>>> 2) standard approach to seeing vorticity would be something >>>> like the following in userchk >>>> >>>> parameter (lt=lx1*ly1*lz1*lelt) >>>> common /myjunk/ vort(lt,3),w1(lt),w2(lt) >>>> logical ifxyt >>>> integer ivout ! flag to turn geometry on/off for VisIt >>>> save ivout >>>> data ivout /0/ >>>> >>>> >>>> if (mod(istep,iostep).eq.0) then >>>> call comp_vort3(vort,w1,w2,vx,vy,vz) >>>> >>>> ifxyt = ifxyo ! put geometry into first vrt file >>>> ifxyo = .false. >>>> if (ivout.eq.0) ifxyo = .true. >>>> ivout = 1 >>>> >>>> call outpost(vort(1,1),vort(1,2),vort(1,3),pr,t,'vrt') >>>> >>>> ifxyo = ifxyt ! restore ifxyo flag to original state >>>> >>>> endif >>>> >>>> >>>> If your session name is blah, this piece of code will put >>>> vorticity into a sequence of files vrtblah0.f0000n >>>> >>>> You can instead ignore the vrt prefix and the part about the >>>> geometry with a simpler code >>>> >>>> parameter (lt=lx1*ly1*lz1*lelt) >>>> common /myjunk/ vort(lt,3),w1(lt),w2(lt) >>>> >>>> if (mod(istep,iostep).eq.0) then >>>> call comp_vort3(vort,w1,w2,vx,vy,vz) >>>> call outpost(vort(1,1),vort(1,2),vort(1,3),pr,t,'vrt') >>>> endif >>>> >>>> I usually go for this latter approach, but the choice is >>>> totally up to you. >>>> >>>> Paul >>>> >>>> >>>> >>>> >>>> >>>> On Fri, 24 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> Hello Paul, >>>>> >>>>> Thanks for your reply. I am looking into the .usr file for >>>>> defining the set_obj (). >>>>> >>>>> 1) Could you please tell me what is 'Enter the number of levels ?' >>>>> in n2to3 >>>>> >>>>> is it the number of elements in Z direction ? >>>>> >>>>> 2) As you said about storing the computed vorticity in velocity >>>>> field to view in VisIT, I found the routine to compute the >>>>> vorticity but I am stuck about adding it to the velocity filed to >>>>> VisIT ? could you please tell me how it works or any example which >>>>> stores vorticity to the .fld file as a separate variable. >>>>> >>>>> >>>>> Thank you >>>>> >>>>> Kamal >>>>> >>>>> >>>>> On 22/01/2014 16:53, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> Axial viscous stress is given by torq_calc -- that's no problem >>>>>> whatsoever. You get a number as a >>>>>> function of time. >>>>>> >>>>>> You can even get stresses on multiple subsets of the geometry >>>>>> (e.g., if you had multiple branches >>>>>> in the domain or multiple cylinders. The drag, which is a >>>>>> byproduct of the torque computation (which >>>>>> you can ignore), is given in terms of the viscous and pressure >>>>>> components separately and as the >>>>>> sum of the two. >>>>>> >>>>>> You can identify domain boundaries by checking the boundary >>>>>> conditions. Here, I recommend >>>>>> looking at the set_obj routines in several of the /example cases. >>>>>> >>>>>> >>>>>> ________________________________________ >>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>> Sent: Wednesday, January 22, 2014 9:37 AM >>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>> >>>>>> Hello Paul >>>>>> >>>>>> I was thinking about taking the tangential velocity near to the >>>>>> wall so that I can figure out my length of the recirculation region. >>>>>> >>>>>> Is it possible for me to access the boundary elements of the mesh >>>>>> ??? so that I can take the boundary element and then obtain the >>>>>> velocity at that point so that I can figure out the length of my >>>>>> recirculation region. >>>>>> >>>>>> or take the *.fld file and read it to plot the datas I need. >>>>>> >>>>>> >>>>>> I also want to calculate the axial viscous force acting on the >>>>>> entire pipe. >>>>>> >>>>>> which is given by >>>>>> >>>>>> C_v = F^v / ( d^2 * rho * U^2 ) = double integral ( 1/Re * (du >>>>>> / dr) ) dtheta dz >>>>>> >>>>>> >>>>>> On Jan 22, 2014, at 4:07 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>>> Hi Kamal, >>>>>>> >>>>>>> As I thought about it some more, if you're interested in the >>>>>>> local wall shear stress >>>>>>> magnitude I'm quite certain you can get this by plotting the >>>>>>> magnitude of vorticity >>>>>>> on the surface in question. (Note that the sign of the WSS, >>>>>>> which in fact is a tensor >>>>>>> or a vector when restricted to a given surface, is lost in this >>>>>>> process, but that might >>>>>>> not be relevant for your needs.) If that works, then you can >>>>>>> readily compute the >>>>>>> vorticity using one of the routines in nek and store the result >>>>>>> in a velocity field, then >>>>>>> view that field with VisIt. Of course WSS will require >>>>>>> multiplication by viscosity. >>>>>>> >>>>>>> hth, >>>>>>> >>>>>>> Paul >>>>>>> >>>>>>> ________________________________________ >>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>>> Sent: Tuesday, January 21, 2014 10:33 AM >>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>> >>>>>>> Hi paul, >>>>>>> >>>>>>> can I make this to be drag or shear quantities to be return to >>>>>>> the a >>>>>>> separate file so that it will easy for me to plot. >>>>>>> >>>>>>> By the way it gives the integral quantity. Think for example I >>>>>>> need to >>>>>>> find the shear stress on the wall from the inlet to outlet at a >>>>>>> particular time = 2 . How can I do that ? >>>>>>> >>>>>>> Is there way to find the number of elements in x,y and z >>>>>>> direction ? >>>>>>> >>>>>>> On 21/01/2014 17:32, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> Hi Kamal, >>>>>>>> >>>>>>>> Your integrated drag quantities should be written to the logfile >>>>>>>> (stdout), >>>>>>>> assuming you've set the arguments in the call to be .true. >>>>>>>> >>>>>>>> Paul >>>>>>>> >>>>>>>> On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> >>>>>>>>> Hi Paul, >>>>>>>>> >>>>>>>>> I checked the set_obj subroutine and implemented one in my >>>>>>>>> .USR file. >>>>>>>>> The code seem to run without any errors but I don't find where >>>>>>>>> these >>>>>>>>> variables are getting stored. >>>>>>>>> >>>>>>>>> I use VisIT to visualize my output, even there was no change >>>>>>>>> in it. >>>>>>>>> >>>>>>>>> do I have to define my own output file and write the variables >>>>>>>>> out ? >>>>>>>>> >>>>>>>>> Thanks, >>>>>>>>> >>>>>>>>> Kamal. >>>>>>>>> >>>>>>>>> >>>>>>>>> On 20/01/2014 21:52, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>> Hi Kamal, >>>>>>>>>> >>>>>>>>>> You'll need to compute your own tke by manipulating the >>>>>>>>>> velocity fields. >>>>>>>>>> >>>>>>>>>> You can get running averages of the requisite quantities >>>>>>>>>> via calls to "avg_all" which is found in navier5.f >>>>>>>>>> >>>>>>>>>> You can compute shear stress on the wall simply by computing >>>>>>>>>> the drag on the wall, which can be done via a call to >>>>>>>>>> torque_calc(), >>>>>>>>>> also found in navier5.f >>>>>>>>>> >>>>>>>>>> If you cd to /examples and type: >>>>>>>>>> >>>>>>>>>> grep torq */*.usr >>>>>>>>>> >>>>>>>>>> you'll find many examples of calls to torque_calc. You simply >>>>>>>>>> need to prescribe the surfaces on which shear is to be >>>>>>>>>> integrated. >>>>>>>>>> >>>>>>>>>> I typically write a routine "set_obj" to identify such surfaces >>>>>>>>>> on the first call to usrchk. >>>>>>>>>> >>>>>>>>>> grep set_obj */*.usr >>>>>>>>>> >>>>>>>>>> will show similar examples. >>>>>>>>>> >>>>>>>>>> I would recommend trying this for laminar Poiseiulle flow in >>>>>>>>>> a very simple channel just to check that your calls are properly >>>>>>>>>> set. >>>>>>>>>> >>>>>>>>>> Best, >>>>>>>>>> >>>>>>>>>> Paul >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>> >>>>>>>>>>> Hi Paul, >>>>>>>>>>> >>>>>>>>>>> Thanks and that helped. >>>>>>>>>>> >>>>>>>>>>> Where can I find the variables like Turbulent KE , shear >>>>>>>>>>> stress on >>>>>>>>>>> the wall. ? >>>>>>>>>>> >>>>>>>>>>> Do i have to activate some parameters for calculating them ? >>>>>>>>>>> >>>>>>>>>>> If I had to plot them. >>>>>>>>>>> >>>>>>>>>>> Thanks, >>>>>>>>>>> Kamal >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> wrote: >>>>>>>>>>> >>>>>>>>>>>> Kamal, >>>>>>>>>>>> >>>>>>>>>>>> Looks good. >>>>>>>>>>>> >>>>>>>>>>>> I'm guessing that one further refinement would be: >>>>>>>>>>>> >>>>>>>>>>>> if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) >>>>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>>>> >>>>>>>>>>>> which would yield >>>>>>>>>>>> >>>>>>>>>>>> scale = 1 when z=z0 >>>>>>>>>>>> scale = smax when z >= z1 >>>>>>>>>>>> >>>>>>>>>>>> Paul >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>> >>>>>>>>>>>>> Hi paul, >>>>>>>>>>>>> >>>>>>>>>>>>> The code works fine, but there should be a small change >>>>>>>>>>>>> thats has >>>>>>>>>>>>> to be done >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >>>>>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>>>>> >>>>>>>>>>>>> This creates a perfect diverging pipe. >>>>>>>>>>>>> >>>>>>>>>>>>> Thanks for the help paul. >>>>>>>>>>>>> >>>>>>>>>>>>> Kamal >>>>>>>>>>>>> >>>>>>>>>>>>> On Jan 20, 2014, at 12:09 AM, >>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>> >>>>>>>>>>>>>> Hi paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> If I am not wrong, >>>>>>>>>>>>>> I make a mesh with three straight pipes( inlet, divergent, >>>>>>>>>>>>>> outlet ) connected together via n2to3 so that I know the >>>>>>>>>>>>>> element >>>>>>>>>>>>>> connectivity places of the divergent section (z0,z1) and >>>>>>>>>>>>>> use the >>>>>>>>>>>>>> section what you gave >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thank you for the code >>>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Jan 19, 2014, at 8:45 PM, >>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I would do the following in usrdat2(): >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> n=nx1*ny1*nz1*nelt >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> do i=1,n >>>>>>>>>>>>>>> x=xm1(i,1,1,1) >>>>>>>>>>>>>>> y=ym1(i,1,1,1) >>>>>>>>>>>>>>> z=ym1(i,1,1,1) >>>>>>>>>>>>>>> scale = 1. >>>>>>>>>>>>>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>>>>>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>>>>>>> xm1(i,1,1,1) = scale*x >>>>>>>>>>>>>>> ym1(i,1,1,1) = scale*y >>>>>>>>>>>>>>> enddo >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Make certain that z1 and z0 correspond to z values >>>>>>>>>>>>>>> that precisely coincide with element interfaces. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I looked into the Peris example but It is so what same >>>>>>>>>>>>>>>> like >>>>>>>>>>>>>>>> the stenosis example with a Cosine deformation. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> In my case it is a pipe with conical divergent. I tried to >>>>>>>>>>>>>>>> play around the variables Xm1, Ym1 and Zm1 but the mapping >>>>>>>>>>>>>>>> doesn't go well. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Could you please help me with this. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> On Jan 18, 2014, at 7:26 PM, >>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I looked at the Helix and stenosis example but they >>>>>>>>>>>>>>>>> are using >>>>>>>>>>>>>>>>> cosine functions to deform >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I tried to use a tangent function but it bends the >>>>>>>>>>>>>>>>> whole pipe. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I dint look at peris example . >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I will take a look at it and let you know. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> On Jan 18, 2014, at 7:22 PM, >>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Have you looked at the peris example? The usr file there >>>>>>>>>>>>>>>>>> shows how to deform >>>>>>>>>>>>>>>>>> a pipe geometry. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Dear Paul, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> I tried many ways to map my straight pipe geometry >>>>>>>>>>>>>>>>>> but it >>>>>>>>>>>>>>>>>> does not seem to work properly >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> I used something like >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> X = X + Z * tan ( alpha ) >>>>>>>>>>>>>>>>>> Y = Y + Z* tan (alpha ) >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> even that dint work. could please help me with this >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Kamal. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> On Jan 17, 2014, at 2:24 PM, >>>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Thanks paul. I tried working with the diverging mesh >>>>>>>>>>>>>>>>>>> modification. >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> z = mx + b >>>>>>>>>>>>>>>>>>> z = ny + c >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> x = ( z - b ) / m >>>>>>>>>>>>>>>>>>> y = (z - c) / n >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Do you think would work ? or is there any other way to >>>>>>>>>>>>>>>>>>> input that ? >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> On 17/01/2014 14:14, >>>>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> 1) To check for convergence, run your simulation for >>>>>>>>>>>>>>>>>>>> increasing polynomial orders ( lx1 in the SIZE >>>>>>>>>>>>>>>>>>>> file) and >>>>>>>>>>>>>>>>>>>> measure some consistent quantity (drag, TKE, etc). You >>>>>>>>>>>>>>>>>>>> can plot this quantity against lx1 and this should >>>>>>>>>>>>>>>>>>>> give >>>>>>>>>>>>>>>>>>>> you a good picture of how you are converging (without >>>>>>>>>>>>>>>>>>>> needing to change the physical mesh). >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> 2) If you weren't using temperature in your >>>>>>>>>>>>>>>>>>>> simulation, >>>>>>>>>>>>>>>>>>>> you could do put the following code snippet in your >>>>>>>>>>>>>>>>>>>> userchk >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>>>>>>> integer i, ntot >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in >>>>>>>>>>>>>>>>>>>> simulation (on THIS processor) >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> do i = 1,ntot >>>>>>>>>>>>>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + >>>>>>>>>>>>>>>>>>>> vz(i,1,1,1)**2) >>>>>>>>>>>>>>>>>>>> enddo >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> ifto = .true. >>>>>>>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> I've assumed here that your density is unity. This >>>>>>>>>>>>>>>>>>>> computed kinetic energy point-wise and stores it in >>>>>>>>>>>>>>>>>>>> the >>>>>>>>>>>>>>>>>>>> temperature field. The part "ifto = .true." tells >>>>>>>>>>>>>>>>>>>> Nek to >>>>>>>>>>>>>>>>>>>> output the temperature field whenever it outputs a >>>>>>>>>>>>>>>>>>>> field >>>>>>>>>>>>>>>>>>>> file. You could then view this in visit just like you >>>>>>>>>>>>>>>>>>>> would the velocity field. >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Hope this helps! >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Josh >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, >>>>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> I will try that mapping, I created a straight pipe >>>>>>>>>>>>>>>>>>>> to do >>>>>>>>>>>>>>>>>>>> some simulations. >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> 1) Is there a way to check my spectral convergence, so >>>>>>>>>>>>>>>>>>>> that I can do some mesh convergence study? >>>>>>>>>>>>>>>>>>>> 2) Is there a way to plot the kinetic energy in the >>>>>>>>>>>>>>>>>>>> flow ? >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> On 15/01/2014 12:14, >>>>>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Hi Kamal, >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> For the geometry you describe, I would apply mesh >>>>>>>>>>>>>>>>>>>> morphing >>>>>>>>>>>>>>>>>>>> to a standard straight pipe. You can create such a >>>>>>>>>>>>>>>>>>>> pipe >>>>>>>>>>>>>>>>>>>> using a subset of the mkmesh script provided in the >>>>>>>>>>>>>>>>>>>> expansion >>>>>>>>>>>>>>>>>>>> example. >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>>>>>>>>>>>>> certain that the change in slope occurs at element >>>>>>>>>>>>>>>>>>>> boundaries, >>>>>>>>>>>>>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> _______________ >>>>>>>>>>>>>>>>>>>> /| | | >>>>>>>>>>>>>>>>>>>> / | | | >>>>>>>>>>>>>>>>>>>> /| | | | >>>>>>>>>>>>>>>>>>>> ________________/ | | | | >>>>>>>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> On Wed, 15 Jan 2014, >>>>>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> I looked at the example and it looks very helpful, >>>>>>>>>>>>>>>>>>>> but for >>>>>>>>>>>>>>>>>>>> a sudden expansion we have only two parts (i.e) the >>>>>>>>>>>>>>>>>>>> inlet >>>>>>>>>>>>>>>>>>>> pipe and the outlet pipe. Whereas in a diverging >>>>>>>>>>>>>>>>>>>> pipe we >>>>>>>>>>>>>>>>>>>> have three section (i.e,) The inlet pipe, Diverging >>>>>>>>>>>>>>>>>>>> section and the outlet pipe. >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Is it possible for me to create a 2D diverging section >>>>>>>>>>>>>>>>>>>> using mesh modification and revolve it around the >>>>>>>>>>>>>>>>>>>> centre >>>>>>>>>>>>>>>>>>>> axis to get a 3d diverging pipe ? >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> or should I apply the mesh modification directly to >>>>>>>>>>>>>>>>>>>> the 3d >>>>>>>>>>>>>>>>>>>> sudden expansion pipe using usrdat2() ? >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> On 14/01/2014 21:09, >>>>>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Thanks a lot for the update. I will take a look at >>>>>>>>>>>>>>>>>>>> as soon >>>>>>>>>>>>>>>>>>>> as possible and keep you updated with it. >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> On Jan 14, 2014, at 9:04 PM, >>>>>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> I've added an example for a step-type expansion in >>>>>>>>>>>>>>>>>>>> a pipe. >>>>>>>>>>>>>>>>>>>> New example directory >>>>>>>>>>>>>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> If you want a standard diffuser, I would use >>>>>>>>>>>>>>>>>>>> mesh-morphing, as outlined in the >>>>>>>>>>>>>>>>>>>> nek primer, which can be found on this page: >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> I've also automated our turbulent outflow bc >>>>>>>>>>>>>>>>>>>> treatment -- >>>>>>>>>>>>>>>>>>>> one simply provides an >>>>>>>>>>>>>>>>>>>> expansion factor (typically ~ 1.5) and two persistent >>>>>>>>>>>>>>>>>>>> arrays to turb_outflow(), which >>>>>>>>>>>>>>>>>>>> is now in navier5.f. This can be useful when very >>>>>>>>>>>>>>>>>>>> strong vortices are leaving the >>>>>>>>>>>>>>>>>>>> domain, which is possible for certain diffuser flow >>>>>>>>>>>>>>>>>>>> conditions (and others). >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>>>>>> ________________________________________ >>>>>>>>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf >>>>>>>>>>>>>>>>>>>> ofnek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Hi >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Can some one please help me in this because I am >>>>>>>>>>>>>>>>>>>> new to nek >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> 1) How can I create a .rea for a specific geometry >>>>>>>>>>>>>>>>>>>> say ' A >>>>>>>>>>>>>>>>>>>> sudden >>>>>>>>>>>>>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> kamal >>>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> -- >>>>>>>>>>>>>>>>>>>> Josh Camp >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> "All that is necessary for the triumph of evil is that >>>>>>>>>>>>>>>>>>>> good men do nothing" -- Edmund Burke >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>> >>>> On Fri, 24 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>> >>>>> Hello Paul, >>>>> >>>>> Thanks for your reply. I am looking into the .usr file for >>>>> defining the set_obj (). >>>>> >>>>> 1) Could you please tell me what is 'Enter the number of levels ?' >>>>> in n2to3 >>>>> >>>>> is it the number of elements in Z direction ? >>>>> >>>>> 2) As you said about storing the computed vorticity in velocity >>>>> field to view in VisIT, I found the routine to compute the >>>>> vorticity but I am stuck about adding it to the velocity filed to >>>>> VisIT ? could you please tell me how it works or any example which >>>>> stores vorticity to the .fld file as a separate variable. >>>>> >>>>> >>>>> Thank you >>>>> >>>>> Kamal >>>>> >>>>> >>>>> On 22/01/2014 16:53, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> Axial viscous stress is given by torq_calc -- that's no problem >>>>>> whatsoever. You get a number as a >>>>>> function of time. >>>>>> >>>>>> You can even get stresses on multiple subsets of the geometry >>>>>> (e.g., if you had multiple branches >>>>>> in the domain or multiple cylinders. The drag, which is a >>>>>> byproduct of the torque computation (which >>>>>> you can ignore), is given in terms of the viscous and pressure >>>>>> components separately and as the >>>>>> sum of the two. >>>>>> >>>>>> You can identify domain boundaries by checking the boundary >>>>>> conditions. Here, I recommend >>>>>> looking at the set_obj routines in several of the /example cases. >>>>>> >>>>>> >>>>>> ________________________________________ >>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>> Sent: Wednesday, January 22, 2014 9:37 AM >>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>> >>>>>> Hello Paul >>>>>> >>>>>> I was thinking about taking the tangential velocity near to the >>>>>> wall so that I can figure out my length of the recirculation region. >>>>>> >>>>>> Is it possible for me to access the boundary elements of the mesh >>>>>> ??? so that I can take the boundary element and then obtain the >>>>>> velocity at that point so that I can figure out the length of my >>>>>> recirculation region. >>>>>> >>>>>> or take the *.fld file and read it to plot the datas I need. >>>>>> >>>>>> >>>>>> I also want to calculate the axial viscous force acting on the >>>>>> entire pipe. >>>>>> >>>>>> which is given by >>>>>> >>>>>> C_v = F^v / ( d^2 * rho * U^2 ) = double integral ( 1/Re * (du >>>>>> / dr) ) dtheta dz >>>>>> >>>>>> >>>>>> On Jan 22, 2014, at 4:07 PM, nek5000-users at lists.mcs.anl.gov wrote: >>>>>> >>>>>>> Hi Kamal, >>>>>>> >>>>>>> As I thought about it some more, if you're interested in the >>>>>>> local wall shear stress >>>>>>> magnitude I'm quite certain you can get this by plotting the >>>>>>> magnitude of vorticity >>>>>>> on the surface in question. (Note that the sign of the WSS, >>>>>>> which in fact is a tensor >>>>>>> or a vector when restricted to a given surface, is lost in this >>>>>>> process, but that might >>>>>>> not be relevant for your needs.) If that works, then you can >>>>>>> readily compute the >>>>>>> vorticity using one of the routines in nek and store the result >>>>>>> in a velocity field, then >>>>>>> view that field with VisIt. Of course WSS will require >>>>>>> multiplication by viscosity. >>>>>>> >>>>>>> hth, >>>>>>> >>>>>>> Paul >>>>>>> >>>>>>> ________________________________________ >>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>> nek5000-users at lists.mcs.anl.gov [nek5000-users at lists.mcs.anl.gov] >>>>>>> Sent: Tuesday, January 21, 2014 10:33 AM >>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>> >>>>>>> Hi paul, >>>>>>> >>>>>>> can I make this to be drag or shear quantities to be return to >>>>>>> the a >>>>>>> separate file so that it will easy for me to plot. >>>>>>> >>>>>>> By the way it gives the integral quantity. Think for example I >>>>>>> need to >>>>>>> find the shear stress on the wall from the inlet to outlet at a >>>>>>> particular time = 2 . How can I do that ? >>>>>>> >>>>>>> Is there way to find the number of elements in x,y and z >>>>>>> direction ? >>>>>>> >>>>>>> On 21/01/2014 17:32, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> Hi Kamal, >>>>>>>> >>>>>>>> Your integrated drag quantities should be written to the logfile >>>>>>>> (stdout), >>>>>>>> assuming you've set the arguments in the call to be .true. >>>>>>>> >>>>>>>> Paul >>>>>>>> >>>>>>>> On Tue, 21 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>> >>>>>>>>> Hi Paul, >>>>>>>>> >>>>>>>>> I checked the set_obj subroutine and implemented one in my >>>>>>>>> .USR file. >>>>>>>>> The code seem to run without any errors but I don't find where >>>>>>>>> these >>>>>>>>> variables are getting stored. >>>>>>>>> >>>>>>>>> I use VisIT to visualize my output, even there was no change >>>>>>>>> in it. >>>>>>>>> >>>>>>>>> do I have to define my own output file and write the variables >>>>>>>>> out ? >>>>>>>>> >>>>>>>>> Thanks, >>>>>>>>> >>>>>>>>> Kamal. >>>>>>>>> >>>>>>>>> >>>>>>>>> On 20/01/2014 21:52, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>> Hi Kamal, >>>>>>>>>> >>>>>>>>>> You'll need to compute your own tke by manipulating the >>>>>>>>>> velocity fields. >>>>>>>>>> >>>>>>>>>> You can get running averages of the requisite quantities >>>>>>>>>> via calls to "avg_all" which is found in navier5.f >>>>>>>>>> >>>>>>>>>> You can compute shear stress on the wall simply by computing >>>>>>>>>> the drag on the wall, which can be done via a call to >>>>>>>>>> torque_calc(), >>>>>>>>>> also found in navier5.f >>>>>>>>>> >>>>>>>>>> If you cd to /examples and type: >>>>>>>>>> >>>>>>>>>> grep torq */*.usr >>>>>>>>>> >>>>>>>>>> you'll find many examples of calls to torque_calc. You simply >>>>>>>>>> need to prescribe the surfaces on which shear is to be >>>>>>>>>> integrated. >>>>>>>>>> >>>>>>>>>> I typically write a routine "set_obj" to identify such surfaces >>>>>>>>>> on the first call to usrchk. >>>>>>>>>> >>>>>>>>>> grep set_obj */*.usr >>>>>>>>>> >>>>>>>>>> will show similar examples. >>>>>>>>>> >>>>>>>>>> I would recommend trying this for laminar Poiseiulle flow in >>>>>>>>>> a very simple channel just to check that your calls are properly >>>>>>>>>> set. >>>>>>>>>> >>>>>>>>>> Best, >>>>>>>>>> >>>>>>>>>> Paul >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On Mon, 20 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>> >>>>>>>>>>> Hi Paul, >>>>>>>>>>> >>>>>>>>>>> Thanks and that helped. >>>>>>>>>>> >>>>>>>>>>> Where can I find the variables like Turbulent KE , shear >>>>>>>>>>> stress on >>>>>>>>>>> the wall. ? >>>>>>>>>>> >>>>>>>>>>> Do i have to activate some parameters for calculating them ? >>>>>>>>>>> >>>>>>>>>>> If I had to plot them. >>>>>>>>>>> >>>>>>>>>>> Thanks, >>>>>>>>>>> Kamal >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> On Jan 20, 2014, at 5:41 AM, nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> wrote: >>>>>>>>>>> >>>>>>>>>>>> Kamal, >>>>>>>>>>>> >>>>>>>>>>>> Looks good. >>>>>>>>>>>> >>>>>>>>>>>> I'm guessing that one further refinement would be: >>>>>>>>>>>> >>>>>>>>>>>> if (z.gt.z0) scale = 1 + (smax-1)*(z-z0)/(z1-z0) >>>>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>>>> >>>>>>>>>>>> which would yield >>>>>>>>>>>> >>>>>>>>>>>> scale = 1 when z=z0 >>>>>>>>>>>> scale = smax when z >= z1 >>>>>>>>>>>> >>>>>>>>>>>> Paul >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>> >>>>>>>>>>>>> Hi paul, >>>>>>>>>>>>> >>>>>>>>>>>>> The code works fine, but there should be a small change >>>>>>>>>>>>> thats has >>>>>>>>>>>>> to be done >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> if (z.gt.z0) scale = 1 + (z /(z1-z0 ))) >>>>>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>>>>> >>>>>>>>>>>>> This creates a perfect diverging pipe. >>>>>>>>>>>>> >>>>>>>>>>>>> Thanks for the help paul. >>>>>>>>>>>>> >>>>>>>>>>>>> Kamal >>>>>>>>>>>>> >>>>>>>>>>>>> On Jan 20, 2014, at 12:09 AM, >>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>> >>>>>>>>>>>>>> Hi paul, >>>>>>>>>>>>>> >>>>>>>>>>>>>> If I am not wrong, >>>>>>>>>>>>>> I make a mesh with three straight pipes( inlet, divergent, >>>>>>>>>>>>>> outlet ) connected together via n2to3 so that I know the >>>>>>>>>>>>>> element >>>>>>>>>>>>>> connectivity places of the divergent section (z0,z1) and >>>>>>>>>>>>>> use the >>>>>>>>>>>>>> section what you gave >>>>>>>>>>>>>> >>>>>>>>>>>>>> Thank you for the code >>>>>>>>>>>>>> >>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Jan 19, 2014, at 8:45 PM, >>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I would do the following in usrdat2(): >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> n=nx1*ny1*nz1*nelt >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> do i=1,n >>>>>>>>>>>>>>> x=xm1(i,1,1,1) >>>>>>>>>>>>>>> y=ym1(i,1,1,1) >>>>>>>>>>>>>>> z=ym1(i,1,1,1) >>>>>>>>>>>>>>> scale = 1. >>>>>>>>>>>>>>> if (z.gt.z0) scale = smax*(z-z0/(z1-z0) >>>>>>>>>>>>>>> if (z.gt.z1) scale = smax >>>>>>>>>>>>>>> xm1(i,1,1,1) = scale*x >>>>>>>>>>>>>>> ym1(i,1,1,1) = scale*y >>>>>>>>>>>>>>> enddo >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Make certain that z1 and z0 correspond to z values >>>>>>>>>>>>>>> that precisely coincide with element interfaces. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> On Sun, 19 Jan 2014, nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> I looked into the Peris example but It is so what same >>>>>>>>>>>>>>>> like >>>>>>>>>>>>>>>> the stenosis example with a Cosine deformation. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> In my case it is a pipe with conical divergent. I tried to >>>>>>>>>>>>>>>> play around the variables Xm1, Ym1 and Zm1 but the mapping >>>>>>>>>>>>>>>> doesn't go well. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Could you please help me with this. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> On Jan 18, 2014, at 7:26 PM, >>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I looked at the Helix and stenosis example but they >>>>>>>>>>>>>>>>> are using >>>>>>>>>>>>>>>>> cosine functions to deform >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I tried to use a tangent function but it bends the >>>>>>>>>>>>>>>>> whole pipe. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I dint look at peris example . >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> I will take a look at it and let you know. >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> On Jan 18, 2014, at 7:22 PM, >>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Have you looked at the peris example? The usr file there >>>>>>>>>>>>>>>>>> shows how to deform >>>>>>>>>>>>>>>>>> a pipe geometry. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf of >>>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>>>>>> Sent: Saturday, January 18, 2014 12:17 PM >>>>>>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> Subject: Re: [Nek5000-users] Pipe with expansion >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Dear Paul, >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> I tried many ways to map my straight pipe geometry >>>>>>>>>>>>>>>>>> but it >>>>>>>>>>>>>>>>>> does not seem to work properly >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> I used something like >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> X = X + Z * tan ( alpha ) >>>>>>>>>>>>>>>>>> Y = Y + Z* tan (alpha ) >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> even that dint work. could please help me with this >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> Kamal. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> On Jan 17, 2014, at 2:24 PM, >>>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Thanks paul. I tried working with the diverging mesh >>>>>>>>>>>>>>>>>>> modification. >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> I tried to use this form of equation to modify the mesh >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> z = mx + b >>>>>>>>>>>>>>>>>>> z = ny + c >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> x = ( z - b ) / m >>>>>>>>>>>>>>>>>>> y = (z - c) / n >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Do you think would work ? or is there any other way to >>>>>>>>>>>>>>>>>>> input that ? >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> On 17/01/2014 14:14, >>>>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.govwrote: >>>>>>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> 1) To check for convergence, run your simulation for >>>>>>>>>>>>>>>>>>>> increasing polynomial orders ( lx1 in the SIZE >>>>>>>>>>>>>>>>>>>> file) and >>>>>>>>>>>>>>>>>>>> measure some consistent quantity (drag, TKE, etc). You >>>>>>>>>>>>>>>>>>>> can plot this quantity against lx1 and this should >>>>>>>>>>>>>>>>>>>> give >>>>>>>>>>>>>>>>>>>> you a good picture of how you are converging (without >>>>>>>>>>>>>>>>>>>> needing to change the physical mesh). >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> 2) If you weren't using temperature in your >>>>>>>>>>>>>>>>>>>> simulation, >>>>>>>>>>>>>>>>>>>> you could do put the following code snippet in your >>>>>>>>>>>>>>>>>>>> userchk >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>>>>>>> integer i, ntot >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> ntot = nx1*ny1*nz1*nelv ! total number of points in >>>>>>>>>>>>>>>>>>>> simulation (on THIS processor) >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> do i = 1,ntot >>>>>>>>>>>>>>>>>>>> t(i,1,1,1,1) = 0.5*(vx(i,1,1,1)**2 + vy(i,1,1,1)**2 + >>>>>>>>>>>>>>>>>>>> vz(i,1,1,1)**2) >>>>>>>>>>>>>>>>>>>> enddo >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> ifto = .true. >>>>>>>>>>>>>>>>>>>> c------------------------------------------- >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> I've assumed here that your density is unity. This >>>>>>>>>>>>>>>>>>>> computed kinetic energy point-wise and stores it in >>>>>>>>>>>>>>>>>>>> the >>>>>>>>>>>>>>>>>>>> temperature field. The part "ifto = .true." tells >>>>>>>>>>>>>>>>>>>> Nek to >>>>>>>>>>>>>>>>>>>> output the temperature field whenever it outputs a >>>>>>>>>>>>>>>>>>>> field >>>>>>>>>>>>>>>>>>>> file. You could then view this in visit just like you >>>>>>>>>>>>>>>>>>>> would the velocity field. >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Hope this helps! >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Josh >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> On Wed, Jan 15, 2014 at 9:52 AM, >>>>>>>>>>>>>>>>>>>> wrote: >>>>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> I will try that mapping, I created a straight pipe >>>>>>>>>>>>>>>>>>>> to do >>>>>>>>>>>>>>>>>>>> some simulations. >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> 1) Is there a way to check my spectral convergence, so >>>>>>>>>>>>>>>>>>>> that I can do some mesh convergence study? >>>>>>>>>>>>>>>>>>>> 2) Is there a way to plot the kinetic energy in the >>>>>>>>>>>>>>>>>>>> flow ? >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> On 15/01/2014 12:14, >>>>>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Hi Kamal, >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> For the geometry you describe, I would apply mesh >>>>>>>>>>>>>>>>>>>> morphing >>>>>>>>>>>>>>>>>>>> to a standard straight pipe. You can create such a >>>>>>>>>>>>>>>>>>>> pipe >>>>>>>>>>>>>>>>>>>> using a subset of the mkmesh script provided in the >>>>>>>>>>>>>>>>>>>> expansion >>>>>>>>>>>>>>>>>>>> example. >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> If your transition region is conical, then I woud make >>>>>>>>>>>>>>>>>>>> certain that the change in slope occurs at element >>>>>>>>>>>>>>>>>>>> boundaries, >>>>>>>>>>>>>>>>>>>> i.e., as in the half cross-section depicted below: >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> _______________ >>>>>>>>>>>>>>>>>>>> /| | | >>>>>>>>>>>>>>>>>>>> / | | | >>>>>>>>>>>>>>>>>>>> /| | | | >>>>>>>>>>>>>>>>>>>> ________________/ | | | | >>>>>>>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>>>>>>> | | | | | | | | >>>>>>>>>>>>>>>>>>>> +-----+-----+---+--+---+------+------+----> z >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> On Wed, 15 Jan 2014, >>>>>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> I looked at the example and it looks very helpful, >>>>>>>>>>>>>>>>>>>> but for >>>>>>>>>>>>>>>>>>>> a sudden expansion we have only two parts (i.e) the >>>>>>>>>>>>>>>>>>>> inlet >>>>>>>>>>>>>>>>>>>> pipe and the outlet pipe. Whereas in a diverging >>>>>>>>>>>>>>>>>>>> pipe we >>>>>>>>>>>>>>>>>>>> have three section (i.e,) The inlet pipe, Diverging >>>>>>>>>>>>>>>>>>>> section and the outlet pipe. >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Is it possible for me to create a 2D diverging section >>>>>>>>>>>>>>>>>>>> using mesh modification and revolve it around the >>>>>>>>>>>>>>>>>>>> centre >>>>>>>>>>>>>>>>>>>> axis to get a 3d diverging pipe ? >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> or should I apply the mesh modification directly to >>>>>>>>>>>>>>>>>>>> the 3d >>>>>>>>>>>>>>>>>>>> sudden expansion pipe using usrdat2() ? >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Thanks, >>>>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> On 14/01/2014 21:09, >>>>>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>>>>>> Hi Paul, >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Thanks a lot for the update. I will take a look at >>>>>>>>>>>>>>>>>>>> as soon >>>>>>>>>>>>>>>>>>>> as possible and keep you updated with it. >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Kamal >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> On Jan 14, 2014, at 9:04 PM, >>>>>>>>>>>>>>>>>>>> nek5000-users at lists.mcs.anl.gov wrote: >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Kamal, >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> I've added an example for a step-type expansion in >>>>>>>>>>>>>>>>>>>> a pipe. >>>>>>>>>>>>>>>>>>>> New example directory >>>>>>>>>>>>>>>>>>>> is nek5_svn/examples/expansion, with a README. >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> If you want a standard diffuser, I would use >>>>>>>>>>>>>>>>>>>> mesh-morphing, as outlined in the >>>>>>>>>>>>>>>>>>>> nek primer, which can be found on this page: >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> http://nek5000.mcs.anl.gov/index.php/UG#Documentation >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> I've also automated our turbulent outflow bc >>>>>>>>>>>>>>>>>>>> treatment -- >>>>>>>>>>>>>>>>>>>> one simply provides an >>>>>>>>>>>>>>>>>>>> expansion factor (typically ~ 1.5) and two persistent >>>>>>>>>>>>>>>>>>>> arrays to turb_outflow(), which >>>>>>>>>>>>>>>>>>>> is now in navier5.f. This can be useful when very >>>>>>>>>>>>>>>>>>>> strong vortices are leaving the >>>>>>>>>>>>>>>>>>>> domain, which is possible for certain diffuser flow >>>>>>>>>>>>>>>>>>>> conditions (and others). >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Paul >>>>>>>>>>>>>>>>>>>> ________________________________________ >>>>>>>>>>>>>>>>>>>> From: nek5000-users-bounces at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>>> [nek5000-users-bounces at lists.mcs.anl.gov] on behalf >>>>>>>>>>>>>>>>>>>> ofnek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>>> [nek5000-users at lists.mcs.anl.gov] >>>>>>>>>>>>>>>>>>>> Sent: Monday, January 13, 2014 3:35 AM >>>>>>>>>>>>>>>>>>>> To: nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>>> Subject: [Nek5000-users] Creating a Mesh >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Hi >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Can some one please help me in this because I am >>>>>>>>>>>>>>>>>>>> new to nek >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> 1) How can I create a .rea for a specific geometry >>>>>>>>>>>>>>>>>>>> say ' A >>>>>>>>>>>>>>>>>>>> sudden >>>>>>>>>>>>>>>>>>>> expansion pipe ' or a ' Diverging pipe ' >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> 2) What tool I should use to create that mesh. >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> Thank you >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> kamal >>>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> -- >>>>>>>>>>>>>>>>>>>> Josh Camp >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> "All that is necessary for the triumph of evil is that >>>>>>>>>>>>>>>>>>>> good men do nothing" -- Edmund Burke >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>>>> >>>>>>>>>>>> _______________________________________________ >>>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> Nek5000-users mailing list >>>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>>>> >>>>>>>>>> _______________________________________________ >>>>>>>>>> Nek5000-users mailing list >>>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> _______________________________________________ >>>>>>>>> Nek5000-users mailing list >>>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Nek5000-users mailing list >>>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>>> _______________________________________________ >>>>>>> Nek5000-users mailing list >>>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>>> _______________________________________________ >>>>>> Nek5000-users mailing list >>>>>> Nek5000-users at lists.mcs.anl.gov >>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>>> _______________________________________________ >>>>> Nek5000-users mailing list >>>>> Nek5000-users at lists.mcs.anl.gov >>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>>>> >>>> _______________________________________________ >>>> Nek5000-users mailing list >>>> Nek5000-users at lists.mcs.anl.gov >>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >>> >>> >>> >>> _______________________________________________ >>> Nek5000-users mailing list >>> Nek5000-users at lists.mcs.anl.gov >>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users >> >> > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users From nek5000-users at lists.mcs.anl.gov Fri Jan 31 11:34:56 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Fri, 31 Jan 2014 18:34:56 +0100 Subject: [Nek5000-users] mesh problems (i think) Message-ID: Dear Neks, I am trying to set up a case from scratch. The goal is to create a complex 3d cylindrical mesh, to start I am trying to build a pipe. 1st attempt: I created a simple 2d 'base.rea' file (by hand) and extruded it with n2to3 to create 'base3.rea'. This case works in 3d, the outer edges are curved and the boundary conditions are correct. 2nd attempt: I wrote a piece of code to create a 3d 'pipe.rea'. I tried to reproduce the case that I had done by hand but this time without success. nek runs the case and produces the usual output without giving any errors but... Problems: - the outer edges are not curved - the boundary conditions are not imposed correctly In both cases I used the same .usr and SIZE files. It seemed to me that I had a problem with face numbering, so I tried changing the number of the curved faces in the pipe.rea file. I tried with all 6 numbers but still no curved faces. I have attached both the 'base3.rea' (which works) and the 'pipe.rea' (which doesn't). I also attached a picture of the output generated when running the 'pipe.rea' case and the SIZE and .usr files. All the attached files can be downloaded from my dropbox folder at this link: https://dl.dropboxusercontent.com/u/18689429/attachment.zip Can someone help me understand why 'pipe.rea' does not work? Best regards, Jacopo -------------- next part -------------- An HTML attachment was scrubbed... URL: From nek5000-users at lists.mcs.anl.gov Fri Jan 31 13:10:43 2014 From: nek5000-users at lists.mcs.anl.gov (nek5000-users at lists.mcs.anl.gov) Date: Fri, 31 Jan 2014 13:10:43 -0600 Subject: [Nek5000-users] mesh problems (i think) In-Reply-To: References: Message-ID: Hi Jacopo, I'm not able to look at your files at this moment, but I do have a quick suggestion. Nek is normally pretty flexible when it comes to the .rea formatting except for boundary conditions and curve sides. I would suggest carefully studying the format of the base3.rea file and make sure the formatting you are using to create pipe.rea is the same. - Josh On Fri, Jan 31, 2014 at 11:34 AM, wrote: > Dear Neks, > I am trying to set up a case from scratch. > The goal is to create a complex 3d cylindrical mesh, to start I am > trying to build a pipe. > > 1st attempt: > I created a simple 2d 'base.rea' file (by hand) and extruded it with > n2to3 to create 'base3.rea'. This case works in 3d, the outer edges are > curved and the boundary conditions are correct. > > 2nd attempt: > I wrote a piece of code to create a 3d 'pipe.rea'. I tried to reproduce > the case that I had done by hand but this time without success. > nek runs the case and produces the usual output without giving any > errors but... > Problems: > - the outer edges are not curved > - the boundary conditions are not imposed correctly > > In both cases I used the same .usr and SIZE files. > > It seemed to me that I had a problem with face numbering, so I tried > changing the number of the curved faces in the pipe.rea file. I tried > with all 6 numbers but still no curved faces. > > I have attached both the 'base3.rea' (which works) and the 'pipe.rea' > (which doesn't). I also attached a picture of the output generated when > running the 'pipe.rea' case and the SIZE and .usr files. > All the attached files can be downloaded from my dropbox folder at this > link: > https://dl.dropboxusercontent.com/u/18689429/attachment.zip > > > Can someone help me understand why 'pipe.rea' does not work? > > Best regards, > Jacopo > > _______________________________________________ > Nek5000-users mailing list > Nek5000-users at lists.mcs.anl.gov > https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users > > -- Josh Camp "All that is necessary for the triumph of evil is that good men do nothing" -- Edmund Burke -------------- next part -------------- An HTML attachment was scrubbed... URL: