[Nek5000-users] CFL's impact on data & 3D without .rea

[nek5000-users at lists.mcs.anl.gov]

Hi Mario,


Please contact me offline at obabko at mcs.anl.gov


Aleks

________________________________
From: Nek5000-users <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, July 9, 2018 12:47:15 PM
To: nek5000-users at lists.mcs.anl.gov
Subject: [Nek5000-users] CFL's impact on data & 3D without .rea


Hello NekGurus,



I have been studying Nek5000 this summer as part of a project investigating it’s viability as a replacement/alternative to other commercial codes.  My two test cases, natural circulation & convective pipe flow, are producing nice results with the only issue being a ‘WARNING: DIV(V)-QTL too large!’  after X time steps.  I’ve increased my targetCFL, from 0.4 to 4.0, and changed dt from variable to fixed.  This has eliminated the warning, at the cost of a longer runtime.  My first question is; will the changes to the CFL value effect the accuracy of temperature or velocity results?

Second, I would like to expand one (or both) of the cases to 3d, do I need to create .rea file to do this, or is it better to import a 3d .STEP file?  I’ve tried using n2to3 and re2torea, but the later outputs the following:



‘At line 70 of file re2torea.f

Fortran runtime error: End of file.’



With an empty .rea file.



It is my impression that the .rea file is no longer necessary.  Is this incorrect?  Please advise on the best way to proceed.



Thank you very much,



Mario



Mario R. Naranjo



Computational Sciences and Engineering

Los Alamos National Laboratory

naranjom at lanl.gov<mailto:naranjom at lanl.gov> | W: 505-664-0978 | M: 505-980-4187


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/nek5000-users/attachments/20180710/c188ee21/attachment.html>