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lindstroem April 12, 2011 10:40

Block with cylinder - BC on a round spot on a surface.
2 Attachment(s)
Hi Everybody!

I want to run a simulation where i want to specify certain boundary conditions on a small spot on one surface - different to the rest of this surface. Therefore i created the attached mesh.
First of all I get a common error "Number of edges not aligned with or perpendicular to non-empty directions". It has to be some edges on the outer rim of the spot, I dont know how to fix it. I also attached the blockMeshDict. Thanks for all suggestions concerning this problem.

In general: Of course I will run some mesh refinements later on, but has anyone experience with similar meshes and maybe some advices? As said, my aim is to specify a individual BC on the round spot. Maybe someone has a complete different idea?

Thanks in advance!

MartinB April 12, 2011 11:54

1 Attachment(s)

you should define some additional blocks. Your block number 10 (counting starts at 0) should be divided into 4 blocks, your block number 0 into 2 blocks. Otherwise the blocks do not match to each other (see orange faces in Paraview screenshot). The non aligned edges should disappear afterwards.

As an alternative you can use mergePatchPairs to merge these blocks, but this might result in non hex elements on the merging faces.

Run checkMesh with additional options

checkMesh -allTopology -allGeometry
since this will give you more warnings and hints.


lindstroem April 13, 2011 04:24

Hi Martin,
thank you very much for your help. I don't get the error any longer. I thought the mesh is important, if it fits, I don't have to care about the blocks. Now, I know it better.
And your right, I prefer not to merge the blocks.

Thank you!

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