I have created a simple 3D beam model and have solved it for static stresses/deflections. No errors, results seem to be as expected. When I then go to create a 2nd scenario to determine the Critical Buckling Load for the model, I get an error during Model Check. The error says "0x6B: Invalid element number 1 in part 2: unexpected 2-node degenerate configuration."
What does this error mean? What do I need to do to DS#2 to get it to run? See attached .ach.
Customer support just responded to a support ticket I logged for this topic. I'm posting their response here to close out this issue.
"Thank you for contacting Autodesk support. The error message you are receiving is caused by a defect related to defining beam orientation. Unfortunately the beam orientation does not correctly copy over and causes the error. The simplest way to resolve the issue to recreate/redefine a new beam orientation."
It worked. Hope to see it fixed in the future. I can foresee situations where this might be very tedious and time consuming.
Did you notice that the displacements in design scenario 1 are not symmetric? (see attached image) As far as I can tell, everything should be symmetric, but you would know your model better than I do.
If it is a discrepancy, it may be caused by the constraints or lack of constraints on your model. There is no constraint that prevents the model from rotating around the Z axis through your top I-beam. When I fixed that rotation, the displacement was about 2/3 of the previous maximum.
Looks like this blog has some good articles for those learning about FEA: http://puny211111.blogspot.com/2012/04/analysis-gu
15 years experience with Simulation Mechanical
Thanks John. The asymmetry of the model is correct. The constraints, as you point out, are not. This is a bit of a test case that I'm using to creep up on the full problem model. Constraining rotation of that beam is necessary and realistic. Thanks.