Learning Forum

[jwynne]

I am trying a basic 3d dynamic mesh simulation before moving to a 3d internal gear simulation. I am rotating the cube in the center counterclockwise at 5 rpm. When I preview the mesh motion, I can see that no remeshing is taking place. The first layer of cells stretches and deforms until there is negative cell volume, throwing an error. I am confused as to why the mesh is not remeshing when the cell parameters reach what I have inputted into the dynamic mesh settings. I have attached my dynamic mesh setup as well as a pre-mesh and post-error mesh image. Any help would be greatly appreciated!

[jwynne]

 

 

[jwynne]

[Federico]

Can you try this with the Unified Remeshing method?

[jwynne]

Thank you for the response.

I tried previewing the motion with unified remeshing (settings attached) and it still seems to be stretching the first layer of elements until negative volume is detected.

 

[Federico]

 

Remeshing is probably happening in the interior regions but you will also need to set the external boundaries to Deforming, i.e. the light grey face seen in your screenshot (and the opposite face on the other side as well).

 

[jwynne]

Frederico,

That appeared to be the problem. The mesh is now updating and is no longer throwing a negative cell volume error. Thank you for your help!

[Federico]

Glad to see that!

If those deforming faces should remain on their plane, you get specify their geometry in the Geometry tab, as described here: 13.6.9.4 Deforming Motion (ansys.com)