[vtkusers] Re: [MayaVi-users] effective stress

[Jose Paulo Moitinho de Almeida]

On Monday 09 December 2002 09:19, Abdel Artoli wrote:
> Dear Sir/Mme,
> Mayavi is a realy nice tool for me.
> I would like to know what are the used formulas for effective stress
> and what is meant by the determinant. Is there a possibility to visualize
> tractions?


"The source has the answer"...

If you get the vtk sources, in Graphics/vtkExtractTensorComponents.cxx you 
will find this code:

      if ( this->ScalarMode == VTK_EXTRACT_EFFECTIVE_STRESS )
        {
        sx = tensor[0];
        sy = tensor[4];
        sz = tensor[8];
        txy = tensor[3];
        tyz = tensor[7];
        txz = tensor[6];

        s = sqrt (0.16666667 * ((sx-sy)*(sx-sy) + (sy-sz)*(sy-sz) +
                                (sz-sx)*(sz-sx) +
                                6.0*(txy*txy + tyz*tyz + txz*txz)));
        }

...................

      else //VTK_EXTRACT_EFFECTIVE_DETERMINANT
        {
        }


The formula for the effective stress is there and nothing for the determinant!

On November 2001 I posted a message to vtkusers 
http://public.kitware.com/pipermail/vtkusers/2001-November/008558.html 
with a patch to define the determinant, but it was never applied.


Regards

Ze Paulo