Hi,

I understand that hex elements are superior than the tet elements, but, can anyone give me a brief summary of the differences?

For complex geometries, most commercial codes use tet meshes. How much accuracy suffers when using tet meshes?

Thanks!

Pei

Yes hex and polyhedral cells are generally superior to tet cells in finite-volume and the difference in both accuracy and convergence behaviour can be large. However, it also depends on the quality of the hex and tet cells and many of the problems with tet meshes stem from the poor quality of some tets produced by many automatic tet mesh generators. In order to really appreciate the difference it might be a good idea for you to try both for your problems. For VOF calculations I would expect the solution on hex/poly cell meshes to be dramatically better.

I do not agree with your statement that "most commercial codes use tet meshes", they certainly support tet meshes but do not use them exclusively and most finite-volume code developers and suppliers recommend the use of hex meshes over tet-meshes if at all possible.

[giuseppe]

HI,
I work also with finite element commercial code: generally the use of tet is based on the existence of automatic tet mesh generation codes.
It is very easy to generate a tet mesh from igs or stp cad complex model !
To increase the accuracy it is suitable to use tet10 elements.


Giuseppe

[hsieh]

Hi, Giuseppe,

Does OpenFOAM supports tet10 element?

Pei

[mattijs]

No. The finiteElement solver has only linear tet elements.

Mattijs