Thin parts in snappyHexMesh
 

Hello,

I have a simple wing with endplates I am trying to mesh. The endplates are quite large in sideview (approx 500x500mm) but thin (4mm) for the most part. I need to allow sHM to use a fine refinement around the rounded leadging and upper edges.

Currently the mesh goes to the highest refinement level (2mm cell size) where the RW endplate is thin, as if it is trying to resolve a gap, but the gap is internal so I do not want this. I cannot see a parameter in the dict file to control this behavior. Is there a way to avoid this without explicitly limiting the refinement in that area (by separating surfaces for example and setting separate refinement levels for each)?

Many thanks.

Greetings Barney,

If you are trying to only use 2 cells for meshing the plate, then you'll have to use a two stage mesh generation strategy. In other words, you will have to first do the castellation and then on another run do the snapping. This is due to the way sHM works. I've reported about this issue several months ago:

• The bug report: http://www.openfoam.com/mantisbt/view.php?id=295
• Mattijs comment on this: http://www.openfoam.com/mantisbt/view.php?id=295#c662
• Latter on I spotted a change that might help: http://www.openfoam.com/mantisbt/view.php?id=295#c671

Another detail is that you have to make sure that a plane of cell faces goes right though the middle of the plate, in order to make sure that sHM can figure out what you want to do.

Best regards,
Bruno

PS: I've seen your other thread about adding layers... and I've seen this as well, but I haven't been able to figure out if it's a bug or not :( This is why I haven't posted anything there.