<div dir="ltr">Philipp and Aleks,<div><br></div><div>Thanks for the replies. The Uzawa method sounds exactly like what I am looking for. I would like to pay a penalty upfront to converge to a good pressure solution without taking too many (or really any) timesteps and then move forward with a resolved pressure solution. I am hoping there is a way to do this since a pressure projection method is being used.</div><div><br></div><div>My solution is already well resolved temporally and I don't want to perturbe it with a long time series of unresolved pressure fields/slightly divergent velocity fields. Can anyone comment on the use of Uzawa with PNPN? Also, Philipp is there a specific routine you call to perform just one of these iterations? I haven't used this method before.</div><div><br></div><div>Kind regards,</div><div><br></div><div>Phil<br><div class="gmail_extra"><br><div class="gmail_quote">On Tue, Jun 14, 2016 at 11:00 AM, <span dir="ltr"><<a href="mailto:nek5000-users-request@lists.mcs.anl.gov" target="_blank">nek5000-users-request@lists.mcs.anl.gov</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Send Nek5000-users mailing list submissions to<br>
<a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a><br>
<br>
To subscribe or unsubscribe via the World Wide Web, visit<br>
<a href="https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users" rel="noreferrer" target="_blank">https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users</a><br>
or, via email, send a message with subject or body 'help' to<br>
<a href="mailto:nek5000-users-request@lists.mcs.anl.gov">nek5000-users-request@lists.mcs.anl.gov</a><br>
<br>
You can reach the person managing the list at<br>
<a href="mailto:nek5000-users-owner@lists.mcs.anl.gov">nek5000-users-owner@lists.mcs.anl.gov</a><br>
<br>
When replying, please edit your Subject line so it is more specific<br>
than "Re: Contents of Nek5000-users digest..."<br>
<br>
<br>
Today's Topics:<br>
<br>
1. Restarting with PNPN using PNPN-2 results<br>
(<a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a>)<br>
2. Re: Restarting with PNPN using PNPN-2 results<br>
(<a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a>)<br>
3. Re: Restarting with PNPN using PNPN-2 results<br>
(<a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a>)<br>
4. Re: lambda2 in turbChannel (<a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a>)<br>
5. g2gi() no geometry found (<a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a>)<br>
6. Re: g2gi() no geometry found (<a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a>)<br>
<br>
<br>
----------------------------------------------------------------------<br>
<br>
Message: 1<br>
Date: Mon, 13 Jun 2016 13:09:05 -0600<br>
From: <a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a><br>
To: <a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a><br>
Subject: [Nek5000-users] Restarting with PNPN using PNPN-2 results<br>
Message-ID:<br>
<<a href="mailto:mailman.23731.1465844987.24727.nek5000-users@lists.mcs.anl.gov">mailman.23731.1465844987.24727.nek5000-users@lists.mcs.anl.gov</a>><br>
Content-Type: text/plain; charset="utf-8"<br>
<br>
Hello neks,<br>
<br>
I have a DNS simulation that I was running as PNPN-2 and I would like to<br>
run it as PNPN without starting back at the initial conditions.<br>
I am curious if anyone has experience running a PNPN case with initial<br>
conditions from a PNPN-2 simulation? I have tried this and the simulation<br>
runs okay, except the pressure term never seems to converge when running<br>
the PNPN simulation. This dramatically increases runtime and makes the<br>
results questionable. It seems to me that restarting with PNPN-2 results<br>
should be doable, and that it should only take a few iterations for the<br>
pressure term to start converging. However, my simulation is still not<br>
converging after 100+ iterations, but it was converging fine when I was<br>
running PNPN-2.<br>
<br>
Any suggestions for things I should look for that might cause the problem,<br>
or potential fixes?<br>
<br>
Thanks<br>
--<br>
Phil Sakievich<br>
<br>
PhD Candidate - Mechanical Engineering<br>
Arizona State University - Ira A. Fulton School for Engineering of Matter<br>
Transport and Energy<br>
Tempe, Arizona<br>
-------------- next part --------------<br>
An HTML attachment was scrubbed...<br>
URL: <<a href="http://lists.mcs.anl.gov/pipermail/nek5000-users/attachments/20160613/790d807b/attachment-0001.html" rel="noreferrer" target="_blank">http://lists.mcs.anl.gov/pipermail/nek5000-users/attachments/20160613/790d807b/attachment-0001.html</a>><br>
<br>
------------------------------<br>
<br>
Message: 2<br>
Date: Mon, 13 Jun 2016 19:15:32 +0000<br>
From: <a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a><br>
To: "<a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a>"<br>
<<a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a>><br>
Subject: Re: [Nek5000-users] Restarting with PNPN using PNPN-2 results<br>
Message-ID:<br>
<<a href="mailto:mailman.23735.1465845499.24727.nek5000-users@lists.mcs.anl.gov">mailman.23735.1465845499.24727.nek5000-users@lists.mcs.anl.gov</a>><br>
Content-Type: text/plain; charset="iso-8859-1"<br>
<br>
Hi Phil,<br>
<br>
The regularity of the pressure field is much larger for Pn-Pn as compared to Pn-Pn-2 so it should take some time to readjust to the larger resolution.<br>
<br>
Aleks<br>
________________________________<br>
From: <a href="mailto:nek5000-users-bounces@lists.mcs.anl.gov">nek5000-users-bounces@lists.mcs.anl.gov</a> [<a href="mailto:nek5000-users-bounces@lists.mcs.anl.gov">nek5000-users-bounces@lists.mcs.anl.gov</a>] on behalf of <a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a> [<a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a>]<br>
Sent: Monday, June 13, 2016 2:09 PM<br>
To: <a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a><br>
Subject: [Nek5000-users] Restarting with PNPN using PNPN-2 results<br>
<br>
Hello neks,<br>
<br>
I have a DNS simulation that I was running as PNPN-2 and I would like to run it as PNPN without starting back at the initial conditions.<br>
I am curious if anyone has experience running a PNPN case with initial conditions from a PNPN-2 simulation? I have tried this and the simulation runs okay, except the pressure term never seems to converge when running the PNPN simulation. This dramatically increases runtime and makes the results questionable. It seems to me that restarting with PNPN-2 results should be doable, and that it should only take a few iterations for the pressure term to start converging. However, my simulation is still not converging after 100+ iterations, but it was converging fine when I was running PNPN-2.<br>
<br>
Any suggestions for things I should look for that might cause the problem, or potential fixes?<br>
<br>
Thanks<br>
--<br>
Phil Sakievich<br>
<br>
PhD Candidate - Mechanical Engineering<br>
Arizona State University - Ira A. Fulton School for Engineering of Matter Transport and Energy<br>
Tempe, Arizona<br>
-------------- next part --------------<br>
An HTML attachment was scrubbed...<br>
URL: <<a href="http://lists.mcs.anl.gov/pipermail/nek5000-users/attachments/20160613/09bbb78b/attachment-0001.html" rel="noreferrer" target="_blank">http://lists.mcs.anl.gov/pipermail/nek5000-users/attachments/20160613/09bbb78b/attachment-0001.html</a>><br>
<br>
------------------------------<br>
<br>
Message: 3<br>
Date: Mon, 13 Jun 2016 21:31:08 +0200<br>
From: <a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a><br>
To: <a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a><br>
Subject: Re: [Nek5000-users] Restarting with PNPN using PNPN-2 results<br>
Message-ID:<br>
<<a href="mailto:mailman.23743.1465847039.24727.nek5000-users@lists.mcs.anl.gov">mailman.23743.1465847039.24727.nek5000-users@lists.mcs.anl.gov</a>><br>
Content-Type: text/plain; charset=windows-1252; format=flowed<br>
<br>
Hi,<br>
<br>
In principle, you can do a Navier-Stokes restart without pressure field.<br>
For PnPn-2 you can for instance do one step with Uzawa (nested<br>
iterations) to have a good pressure. So usually, when we do a restart of<br>
a solution wi<br>
thout pressure (e.g. when doing Arnoldi or Newton) then one Uzawa step<br>
fixes everything. I am not too familiar with PnPn, but I guess that<br>
there is a flavour that is not dependent on a previous pressure<br>
solution. Perhaps a PnPn-expert has some opinion on a Uzawa-like method?<br>
<br>
Best regards,<br>
Philipp<br>
<br>
On 2016-06-13 21:15, <a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a> wrote:<br>
> Hi Phil,<br>
><br>
> The regularity of the pressure field is much larger for Pn-Pn as<br>
> compared to Pn-Pn-2 so it should take some time to readjust to the<br>
> larger resolution.<br>
><br>
> Aleks<br>
> ------------------------------------------------------------------------<br>
> *From:* <a href="mailto:nek5000-users-bounces@lists.mcs.anl.gov">nek5000-users-bounces@lists.mcs.anl.gov</a><br>
> [<a href="mailto:nek5000-users-bounces@lists.mcs.anl.gov">nek5000-users-bounces@lists.mcs.anl.gov</a>] on behalf of<br>
> <a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a> [<a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a>]<br>
> *Sent:* Monday, June 13, 2016 2:09 PM<br>
> *To:* <a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a><br>
> *Subject:* [Nek5000-users] Restarting with PNPN using PNPN-2 results<br>
><br>
> Hello neks,<br>
><br>
> I have a DNS simulation that I was running as PNPN-2 and I would like to<br>
> run it as PNPN without starting back at the initial conditions.<br>
> I am curious if anyone has experience running a PNPN case with initial<br>
> conditions from a PNPN-2 simulation? I have tried this and the<br>
> simulation runs okay, except the pressure term never seems to converge<br>
> when running the PNPN simulation. This dramatically increases runtime<br>
> and makes the results questionable. It seems to me that restarting with<br>
> PNPN-2 results should be doable, and that it should only take a few<br>
> iterations for the pressure term to start converging. However, my<br>
> simulation is still not converging after 100+ iterations, but it was<br>
> converging fine when I was running PNPN-2.<br>
><br>
> Any suggestions for things I should look for that might cause the<br>
> problem, or potential fixes?<br>
><br>
> Thanks<br>
> --<br>
> Phil Sakievich<br>
><br>
> PhD Candidate - Mechanical Engineering<br>
> Arizona State University - Ira A. Fulton School for Engineering of<br>
> Matter Transport and Energy<br>
> Tempe, Arizona<br>
><br>
><br>
> _______________________________________________<br>
> Nek5000-users mailing list<br>
> <a href="mailto:Nek5000-users@lists.mcs.anl.gov">Nek5000-users@lists.mcs.anl.gov</a><br>
> <a href="https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users" rel="noreferrer" target="_blank">https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users</a><br>
><br>
<br>
<br>
------------------------------<br>
<br>
Message: 4<br>
Date: Mon, 13 Jun 2016 16:11:14 -0700<br>
From: <a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a><br>
To: <a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a><br>
Subject: Re: [Nek5000-users] lambda2 in turbChannel<br>
Message-ID:<br>
<<a href="mailto:mailman.23757.1465860244.24727.nek5000-users@lists.mcs.anl.gov">mailman.23757.1465860244.24727.nek5000-users@lists.mcs.anl.gov</a>><br>
Content-Type: text/plain; charset="utf-8"<br>
<br>
Hi Wei,<br>
<br>
I do not think so. But you can definitely, modify the lambda2() routine to<br>
generate the Q criterion. It is quite straightforward.<br>
-------------- next part --------------<br>
An HTML attachment was scrubbed...<br>
URL: <<a href="http://lists.mcs.anl.gov/pipermail/nek5000-users/attachments/20160613/40eedaf9/attachment-0001.html" rel="noreferrer" target="_blank">http://lists.mcs.anl.gov/pipermail/nek5000-users/attachments/20160613/40eedaf9/attachment-0001.html</a>><br>
<br>
------------------------------<br>
<br>
Message: 5<br>
Date: Tue, 14 Jun 2016 11:21:16 +0200<br>
From: <a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a><br>
To: <a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a><br>
Subject: [Nek5000-users] g2gi() no geometry found<br>
Message-ID:<br>
<<a href="mailto:mailman.23773.1465903728.24727.nek5000-users@lists.mcs.anl.gov">mailman.23773.1465903728.24727.nek5000-users@lists.mcs.anl.gov</a>><br>
Content-Type: text/plain; charset=ISO-8859-1; DelSp="Yes";<br>
format="flowed"<br>
<br>
Hello Neks,<br>
<br>
I am trying to use the g2gi subroutine, but keep getting the error<br>
massage ABORT: No geometry found in:<br>
<br>
call userchk<br>
grid-to-grid interpolation<br>
140 8 8 8 2.0010000E+03 4002 U P 4<br>
NELT,NX,N ?a?@<br>
<br>
NONSTD HDR, parse_hdr, abort.<br>
ABORT: No geometry found in newgeom.fld<br>
<br>
call exitt: dying ...<br>
<br>
Anybody familiar with this error? Do I give him the wrong files? I<br>
assumed Nek wants a .fld. Any help or working case as an example would<br>
be highly appreciated.<br>
<br>
Br<br>
Michael<br>
<a href="mailto:e1429308@student.tuwien.ac.at">e1429308@student.tuwien.ac.at</a><br>
<br>
<br>
<br>
<br>
<br>
<br>
------------------------------<br>
<br>
Message: 6<br>
Date: Tue, 14 Jun 2016 11:40:05 +0000<br>
From: <a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a><br>
To: "<a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a>"<br>
<<a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a>><br>
Subject: Re: [Nek5000-users] g2gi() no geometry found<br>
Message-ID:<br>
<<a href="mailto:mailman.23774.1465904407.24727.nek5000-users@lists.mcs.anl.gov">mailman.23774.1465904407.24727.nek5000-users@lists.mcs.anl.gov</a>><br>
Content-Type: text/plain; charset="us-ascii"<br>
<br>
<br>
Hi Michael,<br>
<br>
You need to compile with the ifmpiio flag set in makenek:<br>
<br>
<br>
# (set PPLIST=? to get a list of available symbols)<br>
PPLIST="MPIIO"<br>
<br>
All files should be .f00000 files, which is the current default. (Make certain that your<br>
current .usr file does not reset param(66) to 4.) [ You can convert a .fld file to a .f0000<br>
file by running a 0 step, 0 FINTIME job and setting p66=6, p67=4 in the .usr file, say, in<br>
subroutine usrdat(). ]<br>
<br>
When running g2gi, make certain that the new file has the geometry in it. The old file does not need the<br>
geometry, only the data to be interpolated.<br>
<br>
hth<br>
<br>
Paul<br>
<br>
<br>
________________________________________<br>
From: <a href="mailto:nek5000-users-bounces@lists.mcs.anl.gov">nek5000-users-bounces@lists.mcs.anl.gov</a> [<a href="mailto:nek5000-users-bounces@lists.mcs.anl.gov">nek5000-users-bounces@lists.mcs.anl.gov</a>] on behalf of <a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a> [<a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a>]<br>
Sent: Tuesday, June 14, 2016 4:21 AM<br>
To: <a href="mailto:nek5000-users@lists.mcs.anl.gov">nek5000-users@lists.mcs.anl.gov</a><br>
Subject: [Nek5000-users] g2gi() no geometry found<br>
<br>
Hello Neks,<br>
<br>
I am trying to use the g2gi subroutine, but keep getting the error<br>
massage ABORT: No geometry found in:<br>
<br>
call userchk<br>
grid-to-grid interpolation<br>
140 8 8 8 2.0010000E+03 4002 U P 4<br>
NELT,NX,N ?a?@<br>
<br>
NONSTD HDR, parse_hdr, abort.<br>
ABORT: No geometry found in newgeom.fld<br>
<br>
call exitt: dying ...<br>
<br>
Anybody familiar with this error? Do I give him the wrong files? I<br>
assumed Nek wants a .fld. Any help or working case as an example would<br>
be highly appreciated.<br>
<br>
Br<br>
Michael<br>
<a href="mailto:e1429308@student.tuwien.ac.at">e1429308@student.tuwien.ac.at</a><br>
<br>
<br>
<br>
<br>
_______________________________________________<br>
Nek5000-users mailing list<br>
<a href="mailto:Nek5000-users@lists.mcs.anl.gov">Nek5000-users@lists.mcs.anl.gov</a><br>
<a href="https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users" rel="noreferrer" target="_blank">https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users</a><br>
<br>
<br>
------------------------------<br>
<br>
_______________________________________________<br>
Nek5000-users mailing list<br>
<a href="mailto:Nek5000-users@lists.mcs.anl.gov">Nek5000-users@lists.mcs.anl.gov</a><br>
<a href="https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users" rel="noreferrer" target="_blank">https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users</a><br>
<br>
<br>
End of Nek5000-users Digest, Vol 88, Issue 13<br>
*********************************************<br>
</blockquote></div><br><br clear="all"><div><br></div>-- <br><div class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div>Phil Sakievich</div><div><br></div><div><div>PhD Candidate - Mechanical Engineering</div><div>Arizona State University - Ira A. Fulton School for Engineering of Matter Transport and Energy<br>Tempe, Arizona</div></div></div></div></div></div>
</div></div></div>