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kalyangoparaju July 23, 2012 16:45

Multi Stl snappyHexMesh

I am trying to mesh a geometry with 3 regions ( inlet, porous and outlet). I have 3 closed stl's for all the 3 regions in the triSurface dictionary. When I write the snappyHexMeshDict ( with inspiration from the multi region meshing in chtmultiregionfoam), I define the stls as faceZone and CellZone.

When snappy runs, it detects these face zone and "walks through them" and meshes both inside and outside the pipe ( all 3 regions). When I comment out the faceZone option, it meshes only in the region where the locationInMesh is found.

After some thought, I realized that it might help making the closed surfaces which are the interfaces btween the different stls as faceZone and then let snappy just walk through them build the mesh, theoretically. Unfortunately, that doesn't happen

Is there a better way to do this. In simple words, how to mesh for an internal flow geometry with closed stls by multi region approach using snappyHexMesh.

Hope I was clear. :o


unnikrsn November 15, 2012 06:07

Dear Kalyan

I am working on the same topic to " Mesh Stl files in SnappyHexMesh to get internal faces".. if you have proceeded any further.. Kindly provide the details..

Thanks in advance.

Thanks & regards

GRAUPS November 15, 2012 10:16

1 Attachment(s)
I am also having the exact same issue as you Kalyan. I also posted in this thread referencing this problem.


Originally Posted by GRAUPS (Post 391922)
My case is a cylinder with an inlet region, outlet region, and porous region in the middle. I used three closed stl files to define it.

After meshing, including layer addition, I wish to be able to keep the interfaces between the meshed internal zones as faceZones, that is the main goal. However, it seems like I'm having similar issues as Kalyan had, where it is not crossing over the faceZones correctly and instead of keeping the internal mesh for internal flow and the intersections as faceZones, it meshes the outside domain and only part of the cylinder.

I also gave an example case, which you can find below, that I believe represents the problem Kalyan describes.

Attachment 16990

Does anyone have an explanation as to why what Kalyan describes is happening?

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