Big Difference Between serial run and parallel run case

alundilong · March 19, 2013, 16:46

Hi All,
I'm trying to solve a fluid dynamics problem with modified icoFoam (see attached). Found that different processor running give me very different results. Both solver and cases are attached, please give me any suggestions on what happened. Thank you all in advanced!

francois · March 25, 2013, 09:47

Do you mean that you have different results if you run you case on 1 or n processors ?

JimKnopf · March 28, 2013, 03:12

Which version did you use?

How did you call the solver? Like:

Code:

mpirun -np N icoFoam -parallel >LOG &

SailorLiu · December 5, 2014, 09:27

Hi Yijin,

I know this thread was posted a long time ago but I recently ran into a similar problem. I am using a modified version of interDyMFoam to calculate hydrodynamic force for a heave column with a circular thick plate with prescribed motion pattern. My case can run well in serial mode but if I run it in parallel mode, it will blow out after some time. And the results are also different. I am sure both cases share the same mesh and same settings.
Have you finally found the problem for your case? Any comments or suggestions will be appreciated. Thank you!

Yuanchuan Liu

March 28, 2013, 03:12		#3
JimKnopf Member Jim Knopf Join Date: Dec 2010 Posts: 60 Rep Power: 16	Which version did you use? How did you call the solver? Like: Code: mpirun -np N icoFoam -parallel >LOG &

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March 25, 2013, 09:47		#2
francois Senior Member Francois Beaubert Join Date: Mar 2009 Location: Lille, France Posts: 147 Rep Power: 17	Do you mean that you have different results if you run you case on 1 or n processors ?

December 5, 2014, 09:27		#4
SailorLiu Member Yuanchuan Liu Join Date: Oct 2012 Posts: 31 Rep Power: 14	Hi Yijin, I know this thread was posted a long time ago but I recently ran into a similar problem. I am using a modified version of interDyMFoam to calculate hydrodynamic force for a heave column with a circular thick plate with prescribed motion pattern. My case can run well in serial mode but if I run it in parallel mode, it will blow out after some time. And the results are also different. I am sure both cases share the same mesh and same settings. Have you finally found the problem for your case? Any comments or suggestions will be appreciated. Thank you! Yuanchuan Liu