Meshing Issues

[Anonymous]

Hello All,

I have a model with two different parts, one of them has a little complex geometry. When I set up the model for a static analysis and hit the run button, the model starts running - then it starts meshing - and then it gets stuck at a particular point (most of the times at 95% Meshed). It never exceeds that point. It reaches the 95% mark in about 3 to 4 minutes and then even more than 54 hours latter, it remains at that point. 

The mesh is Brick type with wedges and tetrahedrons. 

Any help to understand the root of the problem and/or directions to a solution are appreciated!

Thanks,

Vikita

[AstroJohnPE]

Hi Vikita,

It sounds like the solid mesher is struggling to fill the volume with elements. It probably went through a number of retries (trying to create an acceptable mesh) during the 54 hours that it was meshing. Here is my suggestion to get it to mesh. 

1. Remesh the model with a slightly smaller mesh size. (Since the interior solid mesh starts with the exterior surface mesh, changing the surface mesh can help with the solid mesh.)
2. Right-click on "CAD Mesh Options" for the first part, then choose "Create Solid Mesh". 
3. On the "Quality" tab, choose "None". (This makes it easier for the mesher to generate the mesh, but the quality of the elements may not be very good. Let's get it to mesh first and then work on the quality!)
4. Click "OK". The solid mesh will be created. You can watch the progress and details to (hopefully) see the number of "faces" go down to zero. If it cannot fill the volume, it will start over again (a retry) and adjust the element shape.
5. If the first part meshes, repeat the process for the second part.

If you cannot get the model to mesh with these settings, then you have a couple of options:

• Try a different surface mesh.
• Split the part that does not mesh into 2 or 3 smaller parts. It should be easier to fill a smaller volume.

Once you get it to mesh, you can check the mesh quality. The line at the end of the mesh statistics (and in the mesh report) shows something like this:

Length ratios (max) 156.2, 62.7, 11.0, 3.6

If the largest value is less than 300, you should be okay.  Even if it is much larger, you might want to run the analysis to see if the analysis gives any warnings (which can occur if elements are severely distorted). If the elements are too distorted, you can repeat the solid mesh and set the Upper Limit for the Quality. (Start with a large value, and reduce it each time to find the limit of what the mesher can do -- if you want to  spend the time to try multiple meshes.)