What does this warning mean

[Anonymous]

I see the warning below and usually do nothing.  But, what does it mean to the results?

"***Warning***

Elements with zero jacobian found, 1 have been removed. 895."

Thanks for any insight

[Anonymous]

When the jacobian is negative, your results will be wrong (how wrong is beyond what I know). The jacobian matrix involves transformation from element cordinates to global cordinates.  The determinant of that matrix will be negative when the elements are greatly distorted.

[Anonymous]

Thanks Jashale for your reply.  Maybe someone else will add some more.  If the results were in question you would think that it would not be a Warning but stop the analysis with a message.

[Anonymous]

Pay attention to the warning. 

"***Warning***

Elements with zero jacobian found, 1 have been removed. 895."

It says it removed the element from the analysis.  If the software kept the bad element then it would have had an effect on your results.

[Anonymous]

Note if the element is in a critical area, you may have problems resolving the max stress in that area.  If its in a noncritical area, don't worry about it.

[zhuangs]

You can check the shape of element 895, and try to remesh this area with finer mesh by adding some refine points here to avoid bad shapes of elements.  This might help avoid the issue.

-Shoubing

[Anonymous]

"You can check the shape of element 895"

How do you locate individual elements in a mesh?  I have not figured this out yet...

[zhuangs]

"Results" ==> "Results Inquire" ==> "Element Information" ==> "Specify" ==> Input "Part Number" and "Element Number" (the element will be selected) ==> Right click and select "Hide unselected elements", then only the selected element is shown.

Right click and select "Show all parts/elements", you can see all the parts and elements.

-Shoubing

[Anonymous]

This is a good thread.  But a somewhat better Warning would be, "Element 895."