[Nek5000-users] Vanishing Jacobian error description

[nek5000-users at lists.mcs.anl.gov]

Michael,

The code is trying to check to ensure that the mesh is
valid.  Sometimes, however, there are other causes for 
the problem.

Can you send a gzip'd rea/usr file, and I can take a look
later tonight.

Paul



On Tue, 20 Apr 2010, nek5000-users at lists.mcs.anl.gov wrote:

> Hi,
>
> I am running into an issue with 'Vanishing Jacobian'. To help understand what the problem
> is, could someone explain what is meant in the error? Specifically, what it means by "Xth node" of the element.
> Also, I ran into this issue when I was deforming geometries in the usr file, where one of the elements
> would overlap another by mistake. However in this case I know there are no overlaps.
>
> Here is a portion:
>
> 0 ERROR: Vanishing Jacobian near 91th node of element 69.
> 1.40692804605498586E-002 -7.79619559165757245E-003
> 0 xyz: 2.65874E-01 3.54498E-01 2.87050E+00
> 0 xyz: 2.07855E-01 1.77249E-01 2.87050E+00
>
>
> 0 ERROR: Vanishing Jacobian near 76th node of element 70.
> 2.59472856644434001E-002 -2.12442422718029170E-002
> 0 xyz: 2.11655E-01 4.23310E-01 2.62500E+00
> 0 xyz: 3.54498E-01 1.77249E-01 2.87050E+00
>
> Thanks for any help deciphering this error!
>
> - Michael
>
>
>
>
>
>