[engg_student]

[New to OpenFoam] I am trying to simulate a concentric tube heat exchanger. I have created the mesh using snappyHexMesh and then used topoSet to divide the mesh into 3 regions (InnerFluid, Pipe and OuterFluid). I don't know why after splitting mesh regions it created patch InnerFluid_to_OuterFluid, but I am sure it has created the patch as it showed on terminal output and on paraview as well.
Now when I run chtMultiRegionFoam, I get following error:

--> FOAM FATAL IO ERROR:
Cannot find patchField entry for InnerFluid_to_OuterFluid

Where does splitMeshRRegions store the patches? I have checked constant/polyMesh/boundary it is not there. I think the patch data is stored in cellToRegion file (which is automatically created when splitting mesh)
Any help would be really appreciated
Thank You!
PS: I am attaching snappyHexMeshDict, blockMeshDict, topoSetDict if you need any other file please let me know

[Yann]

splitMeshRegions splits the mesh and creates news mesh regions stored in constant. So you have to look in constant/InnerFluid/polyMesh/boundary to check for the patches. (or processor*/constant/... if running in parallel)

When splitting the mesh, splitMeshRegions creates interfaces between each region using this syntax "InnerFluid_to_OuterFluid" and in the OuterFluid region you will find the corresponding patch: "OuterFluid_to_InnerFluid"

Yann

[engg_student]

Thanks Yann for your response!
I have figured out the issue. My mesh was not refined enough and therefore some holes were created in the pipe hence leading to formation of OuterFluid_to_InnerFluid patches (which shouldn't have formed in the first place). By refining my issue is resolved (it is not creating OuterFluid_to_InnerFluid patches). Still don't know why it couldn't find the patch it created