<html><head><style type='text/css'>p { margin: 0; }</style></head><body><div style='font-family: Times New Roman; font-size: 12pt; color: #000000'>Oh ok...well then I will try using the bc() array then.<br><br><br>----- Original Message -----<br>From: nek5000-users@lists.mcs.anl.gov<br>To: nek5000-users@lists.mcs.anl.gov<br>Sent: Friday, July 16, 2010 6:06:35 PM GMT -06:00 US/Canada Central<br>Subject: Re: [Nek5000-users] New Recycling BC based on interpolation<br><br><br>Hi Michael,<br><br>Just to be clear - in order for the RBC to work properly inside<br>nek, cbc must be "v ".<br><br>Paul<br><br><br>On Fri, 16 Jul 2010, nek5000-users@lists.mcs.anl.gov wrote:<br><br>> Hi Paul,<br>><br>> Thanks for the emails. At present, it seems easier and more straight forward to use a discriminator for RBC so long as it doesn't effect any other routine (like you mentioned other routines that use 'v '). I think, but could be wrong, that the recycling routine negates using the 'v ' boundary condition for that particular inlet?<br>><br>> I think that as long as the discriminator change doesn't effect anything and at the same time, not calling it 'v ' doesn't cause any issues that the discriminator would be easier.<br>><br>> In the mean time I can try creating the bc() based on cbc and geometry location and use that.<br>><br>> - Michael<br>><br>><br>> ----- Original Message -----<br>> From: nek5000-users@lists.mcs.anl.gov<br>> To: nek5000-users@lists.mcs.anl.gov<br>> Sent: Friday, July 16, 2010 5:32:17 PM GMT -06:00 US/Canada Central<br>> Subject: Re: [Nek5000-users] New Recycling BC based on interpolation<br>><br>><br>> Hi Michael,<br>><br>> As a follow-up --- if you need me to code up a more sophisticated<br>> discriminator, I'm happy to do so.<br>><br>> Paul<br>><br>><br>> On Fri, 16 Jul 2010, nek5000-users@lists.mcs.anl.gov wrote:<br>><br>>><br>>><br>>> Hi Michael,<br>>><br>>> Thanks for the suggestion --- I think it's a good one, but we're<br>>> not quite there yet. I have a couple of comments -<br>>><br>>> Technically "R " is the same as "v " --- because it is a time-space<br>>> varying prescribed Dirichlet condition.<br>>><br>>> Why not simply populate bc(4,f,e,1) with 1,2,3,... to indicate that it is a<br>>> Recycle bc of type 1,2,3,... ? For every cbc, there<br>>> are 6 bc() entries (i.e, bc(k,f,e,1) for k=1 to 6). For "v ", the first one<br>>> of these (k=1) is reserved.<br>>><br>>> That being said, genmap doesn't care about any bc other than "O " and<br>>> "P " (in fact, only "P " at this point), so you could in fact do what<br>>> you propose right now, as long as you replace in usrdat or usrdat2 with<br>>> the functionally correct "v " bc.<br>>><br>>> At present I'm a bit reluctant to make a change to the repo that is<br>>> still in flux w.r.t. development -- There are a few issues to resolve.<br>>> Presumably what one wants to be able to specify is the translation<br>>> distance -- with respect to what? -- and the scale factor as a function<br>>> of time. We have selected w.r.t. to the unit normal on the R face. In<br>>> exact arithmetic there's no difficulty - but in some tricky situations<br>>> there will be problems. Rather than try to engineer a solution for all<br>>> possible scenarios I think it's best to handle this on a case-by-case<br>>> basis until we get a handle on what works and what doesn't.<br>>><br>>> There are also performance issues to be investigated, particularly at<br>>> high processor counts.<br>>><br>>> In a few months I expect we'll have a consolidated code team such<br>>> that we can implement changes (at least the mechanics of them)<br>>> without much difficulty. Right now (through the summer) we're<br>>> a bit saturated.<br>>><br>>> Paul<br>>><br>>><br>>> On Fri, 16 Jul 2010, nek5000-users@lists.mcs.anl.gov wrote:<br>>><br>>>> Oh ok.<br>>>><br>>>> Let's say that I leave one inlet as 'v ', but then change the other<br>>>> inlet to some other variable 'v1 ' or 'X ' or whatever. Would this be<br>>>> ok, without interfering with other routines?<br>>>><br>>>> I suppose where this discussion is heading is: What is the possibility<br>>>> of adding a recycling boundary condition explicity in Nek, such that<br>>>> you can apply it like any other boundary condition, say R for example.<br>>>> So, in the routine you now search for this recycling flag 'R', and<br>>>> then run through the setup, rescale etc...?<br>>>><br>>>> -Michael<br>>>><br>>>> ----- Original Message -----<br>>>> From: nek5000-users@lists.mcs.anl.gov<br>>>> To: nek5000-users@lists.mcs.anl.gov<br>>>> Sent: Friday, July 16, 2010 4:47:11 PM GMT -06:00 US/Canada Central<br>>>> Subject: Re: [Nek5000-users] New Recycling BC based on interpolation<br>>>><br>>>><br>>>> Hi Michael,<br>>>><br>>>> Use whatever discrimination you like --- I would not suggest<br>>>> modifying the character bcs, however, save that you can enter<br>>>> values in bc(k,f,e,1) for k > 1, for any cbc(f,e,1) = 'v '<br>>>><br>>>> The reason for this is that nek checks explicitly for cbc='v '<br>>>> (v, followed by two spaces) in many locations.<br>>>><br>>>> The correct place for discriminating parameters is in the<br>>>> arracy bc().<br>>>><br>>>> Normally I discriminate by geometry --- e.g., x < x0, or<br>>>> something similar, occasionally involving the unit normals on<br>>>> the face in question - as that can be a stronger discriminator.<br>>>><br>>>> Paul<br>>>><br>>>><br>>>> On Fri, 16 Jul 2010, nek5000-users@lists.mcs.anl.gov wrote:<br>>>><br>>>>> Hi Aleks,<br>>>>><br>>>>> Thank you very much for looking into this. I already have a question; I<br>>>>> noticed that you marked several notes dealing with "RBC single inlet --<br>>>>> modify for other cases". I am assuming this means that you have one inlet<br>>>>> that you want to recycle, but another inlet that you do not want to<br>>>>> recycle, which just happens to be my case.<br>>>>><br>>>>> Can I distinguish in the rea between the two by "v1 " and "v2 " without<br>>>>> giving genmap any problems, and then modify the checks in the usr file<br>>>>> accordingly? Also, the subroutine rescale_inflow mentions to modify for<br>>>>> multiple inlets as well but I do not see where any modification<br>>>>> could/needs to be done for it.<br>>>>><br>>>>> - Michael<br>>>>><br>>>>> ----- Original Message -----<br>>>>> From: nek5000-users@lists.mcs.anl.gov<br>>>>> To: nek5000-users@lists.mcs.anl.gov<br>>>>> Sent: Friday, July 16, 2010 3:03:52 PM GMT -06:00 US/Canada Central<br>>>>> Subject: [Nek5000-users] New Recycling BC based on interpolation<br>>>>><br>>>>> Hi Michael and Markus,<br>>>>><br>>>>> Here is a test case for an unsteady pipe flow with Michael's<br>>>>> GambitPipe.rea file which sets inlet Recycling BCs based on interpolation<br>>>>> from a cross-section downstream that you specify by a multiple of the<br>>>>> inlet normal:<br>>>>><br>>>>> http://www.mcs.anl.gov/~obabko/z4.tgz<br>>>>><br>>>>><br>>>>> Let me know if you have any questions.<br>>>>> Best,<br>>>>> Aleks<br>>>>><br>>>>><br>>>>><br>>>>><br>>>>> ----- Original Message -----<br>>>>> From: nek5000-users@lists.mcs.anl.gov<br>>>>> To: nek5000-users@lists.mcs.anl.gov<br>>>>> Sent: Thursday, July 8, 2010 5:06:48 PM GMT -06:00 US/Canada Central<br>>>>> Subject: Re: [Nek5000-users] New Recycling BC method?<br>>>>><br>>>>><br>>>>><br>>>>><br>>>>><br>>>>> No worries, just checkin in to see how it was going, thanks for the<br>>>>> update! Look forward to trying it out!<br>>>>><br>>>>><br>>>>><br>>>>> - Michael<br>>>>><br>>>>> _______________________________________________<br>>>>> Nek5000-users mailing list<br>>>>> Nek5000-users@lists.mcs.anl.gov<br>>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users<br>>>>><br>>>> _______________________________________________<br>>>> Nek5000-users mailing list<br>>>> Nek5000-users@lists.mcs.anl.gov<br>>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users<br>>>><br>>> _______________________________________________<br>>> Nek5000-users mailing list<br>>> Nek5000-users@lists.mcs.anl.gov<br>>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users<br>>><br>> _______________________________________________<br>> Nek5000-users mailing list<br>> Nek5000-users@lists.mcs.anl.gov<br>> https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users<br>><br>_______________________________________________<br>Nek5000-users mailing list<br>Nek5000-users@lists.mcs.anl.gov<br>https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users<br></div></body></html>