[ICEM] Elements with bad angles

Julian121 · June 10, 2018, 02:35

I am using ICEM to generate mesh around a casing treatment.
ICEM finds some elements with angles less than 9 degrees.
I tried to lower the edge criterion from 0.2 to 0.002 but still the bad elements exist.
Can someone please suggest a way to fix the problem?

Gert-Jan · June 10, 2018, 07:16

In your case, there are small gaps where ICEM has problems in generating a prism layer. Why not set proximity to 3 or 5 (=number of tet elements in gap), and use a smaller minimum mesh size.

Julian121 · June 11, 2018, 11:14

Thank you for the suggestion. It did not resolve the problem completely.
I used 3 and 5 elements in gap and left the min size limit as 1.
The prism layers are very irregular around the wall.

Julian121 · June 11, 2018, 11:29

When the mesh is imported in CFX, the mesh gets distorted.
Why does this happen?

Gert-Jan · June 11, 2018, 11:46

It looks like you do not have curves at each edge of all surfaces. You should create these.
The same holds for points. In general, you should have points a all end points of all edges.

ICEM obeys a certain hierarchy. Meaning: it creates a mesh around your geometry and afterwards projects the nodes onto the geoemtry. First it will project to points, then to curves and of none are in the neighborhood of the nodes, it projects them to the surfaces.
So, if your curves are missing, then you get the poor representation of your geometry since the nodes are somewhere floating around on the surface instead of nicely following the edge of the surface.

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June 10, 2018, 07:16		#2
Gert-Jan Senior Member Gert-Jan Join Date: Oct 2012 Location: Europe Posts: 1,827 Rep Power: 27	In your case, there are small gaps where ICEM has problems in generating a prism layer. Why not set proximity to 3 or 5 (=number of tet elements in gap), and use a smaller minimum mesh size.

June 11, 2018, 11:46		#5
Gert-Jan Senior Member Gert-Jan Join Date: Oct 2012 Location: Europe Posts: 1,827 Rep Power: 27	It looks like you do not have curves at each edge of all surfaces. You should create these. The same holds for points. In general, you should have points a all end points of all edges. ICEM obeys a certain hierarchy. Meaning: it creates a mesh around your geometry and afterwards projects the nodes onto the geoemtry. First it will project to points, then to curves and of none are in the neighborhood of the nodes, it projects them to the surfaces. So, if your curves are missing, then you get the poor representation of your geometry since the nodes are somewhere floating around on the surface instead of nicely following the edge of the surface.