CGAL users discussion list

[Mariette Yvinec <>]

Hi Ramin

if your Finite Element Analysis really needs a good quality mesh,
you should also activite others optimisation process.
The best combination is to launch a few Lloyd iterations,
then the perturber, then the exuder

Stephane Tayeb wrote:
> Ramin H wrote:
> > Hi everyone,
> >
> > I am using the Meshe_3 in CGAL 3.6. The meshing criteria is as follows:
> > Cell Aspect Ratio: 3.0
> > Facet Angle: 25
> >
> > And I have turned on Exuding. When I inspect the mesh, I can still see
> > plenty of tetrahedra that are violating the aspect ratio rule. I am 
> > using
> > the resulting mesh for a Finite Element Analysis and the quality of 
> > mesh has
> > a significant impact on the accuracy of the results.
> >
> > How can I get rid of all (or most) of bad tetrahedra?
> >
> > Thanks,
> > -Ramin
>
> Hi Ramin,
>
> After the mesh generation step, you should have a mesh that fulfills 
> your criteria, i.e. every tetrahedron of the mesh should have a 
> *radius-edge ratio <= 3* (is that what you call aspect ratio ?)
>
> As the sliver exudation process tries to increase the smallest 
> dihedral angle in the mesh, there is no guarantee that the radius-edge 
> ratio would not decrease during exudation.
>
> What are your criteria to consider a tetrahedron is bad ?
>
> Best,
> Stéphane.

--
Mariette Yvinec
Geometrica project team
INRIA  Sophia-Antipolis