Trimmed Mesh Cell Quality
 

Good Morning,

How come if you have a perfect cube and you use a trimmed mesh, you will never have all the cells at 100 % quality?

Thank you!

You can certainly mesh a perfect (or very, very closer to it) cube with the trimmer. But you need your cube to align perfectly with the octree mesh.

The trimmer autogenerates a background mesh over objects and then 'trims' out the cells that are not in desired volumes. If the desired volume is perfectly aligned with the background mesh, then you get nearly exactly the perfect background mesh.

Thank you, how do I perfectly align the desired volume with the background mesh then?

I believe that would be a structured mesh and you cannot do that with star-ccm, currently. You would have to mesh using a 3rd party software and import that.

I could be wrong.

You can use "Perform Mesh Alignment" in the trimmer to accomplish what you are describing. The wrapper has this same functionality.

You can use that alignment point as an anchor for the bounding box of the geometry. Look at the documentation for more information.

This will allow you to align the mesh at a particular point, but IMO a superior method is to have the trimmer use a particular coordinate system. You can define a coordinate system under the trimmer mesher object in an operation or continuum. The coordinate system approach allows the background mesh to have any orientation and position.



STAR-CCM+ can make structured meshes via the Directed Mesher. The solver will still treat them as unstructured. They'll have great quality though.