Nastran - Meshing problem using 3D solid elements - No continuity

[esarmientoa]

I’m having an issue when trying to get a continuous mesh using solid elements (Inventor Nastran 2021). I would really appreciate if anyone can help me with this issue.

As an example, I have a simply supported beam, with a distributed vertical load, idealized with solid elements. When I modeled the beam as a single solid, the results are as expected. However, for post-processing purposes, I need to split the solid with different planes. I did this with a single plane, but when doing this, the continuity in the stress fields is lost in the plane of the split, although I meshed with the “Continuous meshing” option activated:

I tried to apply different contacts at the split plane, but it didn’t work in maintaining the continuity in the stress fields, and these are some of the results:

------

As shown before, I haven’t been able to generate continuity in the stress field, and the sudden changes in the stresses are physically incorrect.

How can I generate a continuous mesh using 3D solid elements, in order to get a continuous stress field?

Thank you so much!

Best regards.

[John_Holtz · Accepted solution]

Hi @esarmientoa . Welcome to the Inventor Nastran forum.

You asked "How can I generate a continuous mesh using 3D solid elements, in order to get a continuous stress field?".

Inventor Nastran does not have the capability to mesh solids and match the mesh between different parts. (The label for "Continuous Meshing" indicates it will mesh around the perimeter, but that is not accurate. It generally does not match any nodes between solid parts. Even it that would match around the perimeter, that is not what you want for this model.)

Bonded contact and realizing that results are an approximation at a bonded contact are the best you can do. See Tips 18 and 19 in the PDF document attached to my forum post Suggested Reading - Tips and Tricks on the Inventor Nastran forum.

John