highly skewed elemnts in Gambit
 

Hi,

I am simulating a flow and turbulence problem. The model is a very huge vertical pipe that has two structures which are obstructing flow in the pipe. As they are a bit complicated geometries so I meshed them first. Both have different volume, face and edge meshes.

Now when I try to mesh the transition volume b/w those two (volume connecting those two strucutres) which is basically a pipe, I am getting the highly skewed elemnts. I am used tetmesh though it is a pipe because face and edge meshes on the faces of this volume are very different and can't be coopered. It says "Volume has 24 highly skewed elemnts Equisize skew > 0.97" when I use tetmesh.

I tried splitting this transition into smaller volumes and meshing, which didn't work. I also tried reducing the mesh size, which didn't work either.

What effect does these highly skewed elements have on the results? How can I get rid of them?

Any ideas would be highly appreciated.
Thanks.

1. Viscous discretization may lose accuracy and lead to slow convergence (or diverge).
2. Accurate solution may look oscillatory when plotted.

gory