CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > OpenFOAM > OpenFOAM Running, Solving & CFD

Parallel solution in OpenFOAM

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   September 21, 2009, 09:07
Default Parallel solution in OpenFOAM
  #1
Senior Member
 
Dr. Alexander Vakhrushev
Join Date: Mar 2009
Posts: 256
Blog Entries: 1
Rep Power: 19
makaveli_lcf is on a distinguished road
Send a message via ICQ to makaveli_lcf
Hi all!
As I already wrote at thread http://www.cfd-online.com/Forums/ope...tml#post227242, I noticed a difference between serial and parallel solutions in OpenFOAM. Following pictures illustrate it for 1 CPU and 2 CPUs being used:

1cpu.jpg2cpus.jpg

Velocity magnitude field is shown on both pictures at the end of simulation when we get steady state. Top of the domain is velocity inlet, bottom is pressure outlet, left wall is nonslip with cooled zone where porous media grows due to cooling processes, right is symmetry plain.
For the numerical solution two systems (mass and heat transfer) are solved together until they reach given convergence criteria for each time-step, thus solution is transient.
We can see that for single processor calculations global convergence criteria is fulfilled. When multiprocessor calculations are involved, parallel libraries do not care about global convergence, so from my point of view data is transmitted between subdomains only after each time-step finalization, rather than after each iteration.
So I'm looking for your advises, how to control global convergence of numerical solution for parallel run?
__________________
Best regards,

Dr. Alexander VAKHRUSHEV

Christian Doppler Laboratory for "Metallurgical Applications of Magnetohydrodynamics"

Simulation and Modelling of Metallurgical Processes
Department of Metallurgy
University of Leoben

http://smmp.unileoben.ac.at
makaveli_lcf is offline   Reply With Quote

Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Large test case for running OpenFoam in parallel fhy OpenFOAM Running, Solving & CFD 23 April 6, 2019 10:55
OpenFOAM machine loads for parallel runs hellorishi OpenFOAM Running, Solving & CFD 1 May 27, 2009 18:30
Getting OpenFOAM to coexist with an existing JAVA VM nik777 OpenFOAM Installation 5 February 22, 2007 08:21
Testing of OpenFOAM 1.3alpha Commenced OpenFOAM discussion board administrator OpenFOAM Announcements from ESI-OpenCFD 0 February 7, 2006 08:31
Wall functions Abhijit Tilak Main CFD Forum 6 February 5, 1999 02:16


All times are GMT -4. The time now is 06:39.