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SINGULARITY WITH ADDITION OF STIFFENERS

darrenlovesmusic
Advocate

SINGULARITY WITH ADDITION OF STIFFENERS

darrenlovesmusic
Advocate
Advocate

Hi, 

 

I'm currently completing the Autodesk Nastran (2017) tutorials. For a standard C channel, I was able to get a solution with simple cantilever loading. When I added stiffeners, I get the 5000 singularity error. What could be the issue here? How can I eliminate meshing errors in Autodesk? 

  

Thank You!

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KubliJ
Alumni
Alumni
Accepted solution

Hi @darrenlovesmusic 

 

The screenshots sort of show the issue. I can zoom in a bit and see that your stiffeners are not matched mesh with the rest of the beam. Meaning that they are not connected. You can try turning on Continuous Mesh the meshing dialog box, or try turning on solver contact and setting a MAXAD value that is 10% larger than the large mesh size.

 

Matched Mesh.jpg

 

Thanks,

James

 



James Kubli, P.E.


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darrenlovesmusic
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Hi KubliJ, 

 

You were right there - the solution was to locate the stiffener appropriately, based on the mesh size to avoid overlapping elements at the junctions. I dont know whether its a correct fix, but it worked for me. 

 

Thank you!  

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