[pruthvi1991]

//************ Problem solved ****************// If there are no non-conformal regions then OpenFOAM automatically considers the defaultFaces as an internal region

Hello everyone,

Similar problem here.

I have a structured + unstructured mesh from gmsh. There are a few internal faces which arise due to the hybrid mesh. Basically these are the intersections of different volumes. I'm not sure how to handle them. Importing the mesh to OpenFOAM defines them as follows

defaultFaces
{
type patch;
nFaces 284;
startFace 562756;
}

How must I define these faces in the 0 dictionary?

Here is the github link to the mesh https://github.com/pruthvi1991/gmsh/tree/master/pilot

Thanks,
Pruthvi.

[Linse]

Dear Zahra,

I am sorry for not answering earlier. I have been absent from this forum for a long time due to job-search, finishing reports, etc...

Nevertheless, for what it still might be worth: For your case you might consider a solver like rhoPorousSimpleFoam or porousSimpleFoam (depending if your case should be considered compressible or incompressible).
Probably these are the quickest solution for your case. Although I do not know how far these solvers consider heat transport within the porous phase (if needed).

Cheers,
Bernhard

[Archana V]

Originally Posted by mrshb4

Dear Claudio,

When I said that OF convert internal face into patch, I didn't mean that it must be defined in boundary conditions. Look at this example:

I have a mesh in gambit with one face (and just one face) between 2 volumes and I won't define them as boundaries in gambit. Then bring them in .msh format and use fluentMeshToFoam command to convert that to OF type. In this conversion, OF automatically set that face into a default patch that you should have not define it in /polyMesh/boundary and 0 folder. It is a NEUTRAL interior, and that's it. Just test it.


( If it is 2 faces between 2 volumes it won't be internal face anymore, and you have 2 choices: 1- define both faces in gambit as boundaries that your case would work properly BUT with that BC that is not internal face anymore ( you should define it in /boundary in OF too). 2- not to define them in gambit as boundaries ( and so it won't come to OF boundaries too) that your case would not give you answer properly.)

Hope this helps
Mohammadreza

Hi,

But when you converting to OF then default patch is appearing in the polyMesh/boundary file. Do I have to delete that or I have to keep as it is. Will it appear in the 0 folder while using splitMeshRegions command. Mine is compound mesh generated in salome.


Thanks

[M.W.G.]

Originally Posted by Archana V

Hi,

But when you converting to OF then default patch is appearing in the polyMesh/boundary file. Do I have to delete that or I have to keep as it is. Will it appear in the 0 folder while using splitMeshRegions command. Mine is compound mesh generated in salome.


Thanks

Hi there,

So, did you manage to solve your problem? I am going through the same exact situation now

[zzluozz11]

Hi, I think the solution might be just simple. For the faces are actually interior fliuid, "zeroGradient" type of boundary is suitable.

[emrebnc]

Hello Mohammad, my problem is that when i shace faces in space claim so that there is only one face between two volumes i can not give two different edge sizings to create a nonconformal mesh so ansys automatically creates contact regions. These regions show up in boundary file after fluent3dmeshtofoam conversion. if anyone has overcome this problem i would be very happy to listen to the solution.

Thank you

Originally Posted by mrshb4

Dear Arne
My problem has been solved!!!!
It was easy and I wonder why I couldn't anywhere read about it!!!!
you know my fan(main problem that I want to model) is much complicated than this model.so I cant use diffrent mesh resolution for that!!!I just have to mesh different parts and then with internal faces gather them together.
but it is solved!!!!it is easy.
you should just mesh two volumes separately in gambit(any type of mesh you want),but it is essential that one and just one face should be between 2 volumes, and then when you want to mention boundaries and their types in gambit, dont even choose this internal face. openfoam automatically name it default-patch and finally set it interior face and not a boundary.

anyway
thank youfor your reply

Mohammad