Remove bad mesh quality

Dear Developers,

I have a 3D geometry. I create the mesh using a triangle for the surface and tetrahedral for the volume. I can control the mesh quality for the surface but I obtain several elements in the middle of the geometry with bad quality as can be seen below.

I have tried to use smoothing but it didn’t work. Is it possible to remove the element which has bad quality? I have never done that before. Could anyone please help me with how to do it?

Thank you in advance.
Best regards,
Alvina KK

Is there a geometric constraint that is causing the poor quality? Small curves or surfaces? I would look for those first. Can you composite over the surface or curve?

Which smoothing algorithm did you use? I find that the mean ratio smoother frequently gives the best results. It is an optimization based smoother and can run for a long time on a large mesh.

If you really decide you can live with a gap in the mesh (thermal analysts do this frequently), you can try the following.

Warning: this is a pre-beta type command. Make sure you have a saved copy of the model first so that you can recover in case of a crash.

Look in the command line and the quality command will list the poor quality element id. Enter the following:

set developer on
delete tet <id from the quality command>

Don’t select the tet and then try to delete it. Don’t do a draw tet all or draw tet <id> and try to delete the tet. Those kinds of things are likely to cause a crash.

Dear @karl,
The low angle and complex geometry cause the poor quality. The complex line in the middle of geometry which has low quality as seen in the first figure is a result from the surface webcutting the box (I attach the crosssection figure below).

Previously, I used a condition number scheme to do the smoothing. I just tried mean ratio but received an error : ERROR: Undo group already started. Nested undo groups not supported.

Alvina KK

That is a bug in undo processing. You can type undo group end to close the undo group.