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-   -   Conjugate heat transfer and multiregion (https://www.cfd-online.com/Forums/openfoam/64768-conjugate-heat-transfer-multiregion.html)

akidess May 23, 2009 19:48

Conjugate heat transfer and multiregion
 
Hello everybody!

I was wondering when to use conjugateHeatFoam solver and when to use the chtMultiRegionFoam solver. To me, it looks like the conjugate solver was developed first and then chtMultiregionFoam was developed as its successor to add flexibility, and the conjugateHeatFoam sovler is now kept in the dev-package for legacy reasons. Is that right?

A lot of the information in the forum and on the wiki on CHT seems outdated (if availiabe at all). E.g. I could not get any of the suggested ways to post process multiregion results to work. The solution I found for 1.5 is to use "foamToVTK -region X". For this to work, you have to create a symbolic link constant/X/polyMesh that points to 0.001/X/polyMesh/ for all mesh regions X.

"foamToVTK -cellSet X" runs without any extra labour, however it doesn't seem to load simulation results. Using the -cellSet option will only show the mesh and a cellID variable.

Cheers!
-Anton

Khelian973 June 4, 2009 04:19

Hi Anton

I have the same problem to postprocess the data with chtMultiRegionFoam using ParaFoam... and the tutorial multiRegionHeater
Is it necessary to use VTK? It must exist a solution using ParaFoam i guess, but im just a beginner
Is it possible to find an updated tutorial for this solver?

Kyian

akidess June 4, 2009 13:34

Hello Kyian,

using foamToVTK is the only solution I found. You lose a bit of the convenience paraFoam provides, but it works. Unfortunately I do not know of an updated tutorial.

-Anton

mgc June 5, 2009 07:35

multimesh postprocessing
 
Quote:

Originally Posted by akidess (Post 216985)
I could not get any of the suggested ways to post process multiregion results to work. The solution I found for 1.5 is to use "foamToVTK -region X". For this to work, you have to create a symbolic link constant/X/polyMesh that points to 0.001/X/polyMesh/ for all mesh regions X.


Hi Anton,

I work with several meshes. For postprocessing I convert the foam results into ".vtk".

If the structure of your case is like the one of ../tutorials/conjugateHeatFoam/conjugateCavity, then try doing:

1.- For main mesh (region0)
~/.../caseDirectory $ foamToVTK -case caseName

2.- For other meshes
~/.../caseDirectory $ foamToVTK -case caseName -region otherMeshName

3.- Visualization with ParaView
Open: caseDirectory/CaseName/VTK/caseName*.vtk
Open: caseDirectory/CaseName/VTK/otherMeshName/caseName*.vtk
Use Paraview filter: GroupDataSet to join both meshes results.

It should work.

Be careful with the symbolic link!!
- caseDirectory/caseName/constant/polyMesh is the main mesh (region0).
- caseDirectory/caseName/constant/solid is a symbolic link BUT it points to the caseDirectory/solid/constant, where the polyMesh of the solidMesh is located (solidMesh = otherMeshName).

Marķa

akidess August 13, 2009 14:27

Hello Maria,

sorry for the late response. I took a break from the CHT stuff for a bit while I was busy with other things. Thanks a lot for the tip with GroupDataSet, it was very helpful.

Anton

msarkar January 8, 2010 00:45

Conjugate heat transfer
 
Hello All,

I am new in OpenFOAM but not in CFD. I am using OpenFOAM-1.5. Need to simulate 2D conjugate heat transfer. Could anyone guide me how to approach it as there is no tutorials available? I think it can be simulated using chtMultiregionFoam solver but how to use it?

Thanks a lot!!

mik March 11, 2010 05:53

conjugate heat transfer
 
Hi all,

I have the same problem, i want to simulate the "MultiRegionHeater" tutorials but I don't know if I have to use "blockMesh" and the solver "chtMultiRegionFoam" doesn't work!

The error is:
---------------------------------------------------------------------------------------------------------
Cannot find file "points" in directory "constant/bottomAir/polyMesh"

From function Time::findInstance(const fileName&, const word&, const IOobject::readOption)
in file db/Time/findInstance.C at line 148.
---------------------------------------------------------------------------------------------------------

Some one can help us?

Thanks a lot!

Mik

FOAM exiting

kawuppdich March 11, 2010 09:47

look at the Allrun file in the tutorial. There you can see what to do step by step. Also look here http://www.tfd.chalmers.se/~hani/kurser/OS_CFD_2008/chtFoam.pdf

mik March 12, 2010 11:10

Conjugate heat transfer
 

Hi Kawuppdich
, Thanks for the documents,
thanks to this and two commands I have run the simulation!

I have still problems with the simulation and open paraview!

I don't understand what I have to do for open the simulation.
Theoretically it is explained in the last page but I don't understand this command at all!

The last page name is: "Running and visualizing the result" and except for the first point I don't manage to do it!
What I have to do, re-merge the mesh?

It is open-source VTK ?

Thaks

Mik



kawuppdich March 12, 2010 11:31

nice that i could help, I had trouble too with this solver

in of16 in the Allrun is a good way to see the results

there you touch each region. Then you have to start paraview with
Code:

paraview
and then you can open the .OpenFOAM files to view each result. It is possible to open more than one region at the same time.

greetings

Antoine89 July 25, 2013 04:52

Quote:

Originally Posted by mik (Post 249720)

Hi Kawuppdich
, Thanks for the documents,
thanks to this and two commands I have run the simulation!

Hi mik,
I know that it's been a while but could you tell me which commands you wrote to run the simulation cause I don't find in this .pdf file why I'm wrong.

thanks a lot

Rgds

AA


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