Meshing errors

[Jlog50]

Hello all,

I am trying to conduct FE model of complex bone models (see

http://www.eng-tips.com/viewthread.cfm?qid=284706&page=1)

and seem to facing some issues I believe due to the complex geometry, I try to make adjustments to part seeds, however, the following error message is obtained when I try to run the analysis...

***ERROR: The volume of 8 elements is zero, small, or negative. Check coordinates or node numbering, or modify the mesh seed. In the case of a tetrahedron this error may indicate that all nodes are located very nearly in a plane. The elements have been identified in element set ErrElemVolSmallNegZero.

Also for various nodes I have the following warnings

***WARNING: NODE 52 INSTANCE PART_1 ON SURFACE ASSEMBLY__PICKEDSURF10 HAS FACETS WITH NORMAL VECTORS DIFFERING BY MORE THAN 30 DEGREES. CONVERGENCE DIFFICULTIES MAY OCCUR AT THIS NODE WITH FINITE-SLIDING CONTACT. THE NORMAL CONTACT DIRECTION AT THIS NODE WILL BE (0.51820,-0.51820,-0.68039).

***WARNING: 71 elements are distorted. Either the isoparametric angles are out of the suggested limits or the triangular or tetrahedral quality measure is bad. The elements have been identified in element set WarnElemDistorted.

Does anyone have any input on solving these modelling issues, particularly the ERROR message.

Thanks

 

[corus]

I downloaded the geometry from the link you gave and meshed the two parts using 6.10.1. Other than a few elements that had warnings given, there were no elements that had errors. It might be better to remove the mesh (to reduce the file size) and upload the cae file for others to see.

Tata

 

[Jlog50]

Solved this issue, for some reason, if I applied finite sliding (surface to surface) interaction rather than small sliding the error message disappeared? Not sure why? I also had to select to allow adjustment to remove overclosure.

Thank-you very much for your input on this.

 

[mchaudhary]

Hi Jlog50,

Can you please explain in detail how you solved this issue? I encountered the exact same error.

Your help with this is greatly appreciated.