How Can I control the first volume mesh??

tmddnjs0727 · April 4, 2022, 02:33

Hello, everyone..

I need your tips..

The first volume mesh is so big.. I know I have to make the growth rate gradually.. so..

How can I control the volume mesh size after prism layer?? and then, How can I make my mesh grow gradually?

without controlling the prism layer total thickness..

LuckyTran · April 4, 2022, 06:10

Actually, the first volume cell is roughly the same as the surface size. This much has nothing to do with a gradual change in volume meshing characteristics. You should be tweaking the target surface size and prism layer thickness to get a more gradual transition there. Lowering the target surface size of course will greatly increase the cell count if you don't do other things.

The other two properties you need to look for is the maximum tet size and volume growth ratio. The maximum tet size controls the size of the core mesh. The default is 100% of the base size. You can change this to have the core mesh cells bigger/smaller than the typical surface size. The volume growth ratio is the parameter you're asking about. The default value is already quite low. But you can lower it down to 1.1 if you want a super slow growth. But the volume growth controls the core mesh changes from one volume cell to the next. The abrupt change between prism layer and volume will still be present until you do what is noted before.

tmddnjs0727 · April 4, 2022, 09:28

It means, when I want to make the mesh gradually, on the point which changes from prism mesh to volume mesh(first volume mesh), I have to change the surface target size and prism total thickness.

It' very helpful for me Thank you for your answering.. I had just controlled the maximum tet size and volume growth rate..

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April 4, 2022, 06:10		#2
LuckyTran Senior Member Lucky Join Date: Apr 2011 Location: Orlando, FL USA Posts: 5,761 Rep Power: 66	Actually, the first volume cell is roughly the same as the surface size. This much has nothing to do with a gradual change in volume meshing characteristics. You should be tweaking the target surface size and prism layer thickness to get a more gradual transition there. Lowering the target surface size of course will greatly increase the cell count if you don't do other things. The other two properties you need to look for is the maximum tet size and volume growth ratio. The maximum tet size controls the size of the core mesh. The default is 100% of the base size. You can change this to have the core mesh cells bigger/smaller than the typical surface size. The volume growth ratio is the parameter you're asking about. The default value is already quite low. But you can lower it down to 1.1 if you want a super slow growth. But the volume growth controls the core mesh changes from one volume cell to the next. The abrupt change between prism layer and volume will still be present until you do what is noted before.

April 4, 2022, 09:28		#3
tmddnjs0727 New Member Seung Won Lee Join Date: Mar 2022 Location: I live in Seoul, Southern Korean Posts: 2 Rep Power: 0	It means, when I want to make the mesh gradually, on the point which changes from prism mesh to volume mesh(first volume mesh), I have to change the surface target size and prism total thickness. It' very helpful for me Thank you for your answering.. I had just controlled the maximum tet size and volume growth rate..