non reproducible results with respect to domain decomposition

vinch · January 17, 2015, 20:44

Hi guys,
I'm doing simple tests using the application BuoyantBoussinesqPimpleFoam. It's basically the same example than the hot room given, where I added an inflow on every sides of the box.
However, I did the exact same simulation on 24 processors, but specifying in system/decomposeParDict a different domain decomposition. I used the following:
(24 1 1)
(6 4 1)
(4 6 1)

I joined to this message the results of the simulations at an equal time. The plots are showing a cut in the z direction. On the left hand side, the Uz component of the velocity is given, and on the right hand side, mag(U) is given.

We can see that Uz changes from a simulation to another.
I also joined a decomposeParDict file I use as text file.

Did anybody experienced the same problem? Is there a way to fix that?

no_forcing_1.jpg

no_forcing_2.jpg

no_forcing_3.jpg

decomposeParDict.txt

Venu Angirekula · October 18, 2021, 09:57

Hi Vinci,

Did found the reason for the not able to reproducibility results with different processors.

HPE · November 4, 2021, 14:22

Could any of you provide a reproducible example for this?

January 17, 2015, 20:44	non reproducible results with respect to domain decomposition	#1
vinch New Member vinch Join Date: Dec 2011 Posts: 4 Rep Power: 14	Hi guys, I'm doing simple tests using the application BuoyantBoussinesqPimpleFoam. It's basically the same example than the hot room given, where I added an inflow on every sides of the box. However, I did the exact same simulation on 24 processors, but specifying in system/decomposeParDict a different domain decomposition. I used the following: (24 1 1) (6 4 1) (4 6 1) I joined to this message the results of the simulations at an equal time. The plots are showing a cut in the z direction. On the left hand side, the Uz component of the velocity is given, and on the right hand side, mag(U) is given. We can see that Uz changes from a simulation to another. I also joined a decomposeParDict file I use as text file. Did anybody experienced the same problem? Is there a way to fix that? no_forcing_1.jpg no_forcing_2.jpg no_forcing_3.jpg decomposeParDict.txt

October 18, 2021, 09:57	Any solution?	#2
Venu Angirekula New Member venu Join Date: May 2019 Posts: 7 Rep Power: 6	Hi Vinci, Did found the reason for the not able to reproducibility results with different processors.

November 4, 2021, 14:22		#3
HPE Senior Member Herpes Free Engineer Join Date: Sep 2019 Location: The Home Under The Ground with the Lost Boys Posts: 932 Rep Power: 12	Could any of you provide a reproducible example for this? __________________ The OpenFOAM community is the biggest contributor to OpenFOAM: User guide/Wiki-1/Wiki-2/Code guide/Code Wiki/Journal Nilsson/Guerrero/Holzinger/Holzmann/Nagy/Santos/Nozaki/Jasak/Primer Governance Bugs/Features: OpenFOAM (ESI-OpenCFD-Trademark) Bugs/Features: FOAM-Extend (Wikki-FSB) Bugs: OpenFOAM.org How to create a MWE New: Forkable OpenFOAM mirror

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
[snappyHexMesh] How to define to right point for locationInMesh	Mirage12	OpenFOAM Meshing & Mesh Conversion	7	March 13, 2016 14:07
Waterwheel shaped turbine inside a pipe simulation problem	mshahed91	CFX	3	January 10, 2015 11:19
Floating point exception: Zero divide	liladhar	CFX	11	December 16, 2013 04:07
Vertical Axis Wind Turbine Rotating Domain Problems	TWaung	CFX	4	May 1, 2012 03:14
air bubble is disappear increasing time using vof	xujjun	CFX	9	June 9, 2009 07:59