[ICEM] how to avoid mesh elements in gap?

harshavardhanps383 · March 7, 2021, 23:29

I was making a Tet mesh to a geometry that had a very narrow gap between two surfaces. After generating mesh, the mesh elements are going inside the gap. How to avoid that?
I am attaching images below.

Gert-Jan · March 8, 2021, 02:20

Remove all points and curves that are not necessary to represent your geometry.

harshavardhanps383 · March 8, 2021, 02:41

Thank you for your reply sir.
I removed all curves and points and done 'built topology' and set surface max size to all surfaces and done octree mesh.

Gert-Jan · March 8, 2021, 02:57

Tr increasing your minimum size

harshavardhanps383 · March 8, 2021, 04:01

Sir, I was given different surface mesh sizes. When I do surface mesh that hole is capturing well. when I do volume mesh by Delaunay that is not capturing well in volume mesh. What to do sir? ( I have given 0.1mm for that thin wall edge)

Gert-Jan · March 8, 2021, 05:08

1) If there is a hole, then close it with a surface. Remove all curves and points that are unnecessary to describe your geometry.

2) I never use Delauney, so I don't know.

3) Use Robust Octree.
Go to Global Mesh Setup. Disable Curvature/Proximity Based Refinement. And off you go.

4) In you first post, you have written something in red on a blue backgrund. Impossible to read. And where is this in your geometry. It is unclear to me

harshavardhanps383 · March 8, 2021, 05:40

Sir, I am attaching the figure. That gap should be maintained in my geometry.
In surface mesh, it is capturing well but in volume mesh, it is not capturing.
I tried edge criteria of 0.02 and defined thin cuts also. still problem not solved.

Gert-Jan · March 8, 2021, 06:13

Better not include the gap. Why not make it an internal surface? That is much more efficient:
1) Reduce it to a single surface
2) Give it a unique name
3) Go to: Mesh > Part Mesh Setup > Internal Wall or Split Wall

And off you go.

harshavardhanps383 · March 8, 2021, 06:41

Sir, actually we made a gap because prism layers transition will be good. Is it possible prism layer transition will be good at a sharp corner( without gap). Those two are walls with a 1mm gap.

Gert-Jan · March 8, 2021, 08:00

You can extent the surface at the tip, give the extention a unique name, apply inflation (prisms) on it, but in the modelling, do not define it as a wall.
The prisms on the extention, hanging in the volume around the tip will be part of your volume mess, which should be completely fine.

March 8, 2021, 05:08		#6
Gert-Jan Senior Member Gert-Jan Join Date: Oct 2012 Location: Europe Posts: 1,827 Rep Power: 27	1) If there is a hole, then close it with a surface. Remove all curves and points that are unnecessary to describe your geometry. 2) I never use Delauney, so I don't know. 3) Use Robust Octree. Go to Global Mesh Setup. Disable Curvature/Proximity Based Refinement. And off you go. 4) In you first post, you have written something in red on a blue backgrund. Impossible to read. And where is this in your geometry. It is unclear to me aero_head likes this.

March 8, 2021, 06:13		#8
Gert-Jan Senior Member Gert-Jan Join Date: Oct 2012 Location: Europe Posts: 1,827 Rep Power: 27	Better not include the gap. Why not make it an internal surface? That is much more efficient: 1) Reduce it to a single surface 2) Give it a unique name 3) Go to: Mesh > Part Mesh Setup > Internal Wall or Split Wall And off you go. aero_head likes this.

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March 8, 2021, 02:20		#2
Gert-Jan Senior Member Gert-Jan Join Date: Oct 2012 Location: Europe Posts: 1,827 Rep Power: 27	Remove all points and curves that are not necessary to represent your geometry.

March 8, 2021, 02:41		#3
harshavardhanps383 New Member Iharshavardhan reddy Join Date: Dec 2020 Posts: 17 Rep Power: 5	Thank you for your reply sir. I removed all curves and points and done 'built topology' and set surface max size to all surfaces and done octree mesh.

March 8, 2021, 02:57		#4
Gert-Jan Senior Member Gert-Jan Join Date: Oct 2012 Location: Europe Posts: 1,827 Rep Power: 27	Tr increasing your minimum size

March 8, 2021, 04:01		#5
harshavardhanps383 New Member Iharshavardhan reddy Join Date: Dec 2020 Posts: 17 Rep Power: 5	Sir, I was given different surface mesh sizes. When I do surface mesh that hole is capturing well. when I do volume mesh by Delaunay that is not capturing well in volume mesh. What to do sir? ( I have given 0.1mm for that thin wall edge)

March 8, 2021, 06:41		#9
harshavardhanps383 New Member Iharshavardhan reddy Join Date: Dec 2020 Posts: 17 Rep Power: 5	Sir, actually we made a gap because prism layers transition will be good. Is it possible prism layer transition will be good at a sharp corner( without gap). Those two are walls with a 1mm gap.

March 8, 2021, 08:00		#10
Gert-Jan Senior Member Gert-Jan Join Date: Oct 2012 Location: Europe Posts: 1,827 Rep Power: 27	You can extent the surface at the tip, give the extention a unique name, apply inflation (prisms) on it, but in the modelling, do not define it as a wall. The prisms on the extention, hanging in the volume around the tip will be part of your volume mess, which should be completely fine.