SnappyHexMesh plane surface bounding box

mattijs · August 21, 2009, 08:15

This should work. Check that your locationInMesh is inside a cell and inside the part you want to keep. The minVol setting in meshQualityControls will not affect refinement. only snapping and layering.

andresbh · August 26, 2009, 07:13

Hi Mattijs,

thank you for your reply. I double checked that locationInMesh is inside the part I want to keep. I deployed snappyhexmesh again and I ran a simulation with the resulting mesh.

In the following figure you see a slide through the domain. Here the circular white lines represent the outer part of my stl body. Inside in red is what should have been removed. The speed in these red regions is zero with a wall-like behavior outside the withe lines which is feasable. I could live with this but the problem are those regions inside the circles with a non-zero velocity.

screensh.jpg

Have you got any experience with something like this?

I also attach my blockmeshdict and snappyhexmeshdict so that you can make yourself a better idea of my settings. I cant upload my stl file because it is quite large.

snappyHexMeshDict.txt
blockMeshDict.txt

Thank you again for your help

cheers
Andres

mattijs · August 26, 2009, 08:34

Looks like your stl isn't closed enough and the mesh has 'bled' through (the mesher does ray intersection tests to determine hits on the surface). Run surfaceCheck on your individual stls and check for edges with <>2 faces. Fix or perturb your stls and try again.

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August 21, 2009, 08:15		#21
mattijs Senior Member Mattijs Janssens Join Date: Mar 2009 Posts: 1,419 Rep Power: 26	This should work. Check that your locationInMesh is inside a cell and inside the part you want to keep. The minVol setting in meshQualityControls will not affect refinement. only snapping and layering.

August 26, 2009, 07:13		#22
andresbh New Member andres Join Date: Aug 2009 Posts: 15 Rep Power: 17	Hi Mattijs, thank you for your reply. I double checked that locationInMesh is inside the part I want to keep. I deployed snappyhexmesh again and I ran a simulation with the resulting mesh. In the following figure you see a slide through the domain. Here the circular white lines represent the outer part of my stl body. Inside in red is what should have been removed. The speed in these red regions is zero with a wall-like behavior outside the withe lines which is feasable. I could live with this but the problem are those regions inside the circles with a non-zero velocity. screensh.jpg Have you got any experience with something like this? I also attach my blockmeshdict and snappyhexmeshdict so that you can make yourself a better idea of my settings. I cant upload my stl file because it is quite large. snappyHexMeshDict.txt blockMeshDict.txt Thank you again for your help cheers Andres

August 26, 2009, 08:34		#23
mattijs Senior Member Mattijs Janssens Join Date: Mar 2009 Posts: 1,419 Rep Power: 26	Looks like your stl isn't closed enough and the mesh has 'bled' through (the mesher does ray intersection tests to determine hits on the surface). Run surfaceCheck on your individual stls and check for edges with <>2 faces. Fix or perturb your stls and try again.