Running Analysis on a frame solid beam elements instead of line elements

[Anonymous]

I'm trying to run analysis on a roll cage that was generated by Inventor's Frame Generator in Nastran with solid beam elements instead of line elements because there is some speculation that the line elements will not showcase the complex geometry associated with the tube - tube joints. However, whenever I run the analysis with solid beam elements I get fatal error 5004. I've tried changing my contact distance and manual contacts but I still can't get it to complete. 

The beam elements important into nastran as line elements but then I change them to solid elements and mesh the whole thing together. 

[John_Holtz]

Hi @Anonymous 

Sorry for the delay in responding.

These are the most common reasons for singularity type errors (E5000, E5001, E5004, depending on the analysis) during the analysis:

1. The model is not statically stable because of lack of constraints.
2. Some piece of the model is not statically stable because of missing contact.
3. The mesh is distorted.
4. The material properties are incorrect, or the range of maximum stiffness divided by minimum stiffness is too large (such as modeling putty in one piece and "no-bendium" in another part.)

You can change the analysis type to Normal Modes and calculate the natural frequency. If the problem is 1 or 2, the first few modes with be 0 Hz, and the deformation will show which part is moving freely. If the modal analysis fails, then the problem is 3 or 4.

Let us know what you find out.