Mesh orientation and negative volumes
 

Hi All,

I'm simulating a 3d airfoil in cfx using icem mesher. I have a problem in cfx solver, I either get negative volumes or floating point overflow errors. It's very frustrating as I've changed things around many times to no avail.
Could mesh orientation cause these errors? I mean if you have some right-handed and some left-handed elements would the solution fail?
Also how can I get rid of negative volume elements? Many thanks.
Nick

If you do too much smoothing with ICEM you can get negative volume elements. Be very careful with your smoothing.

Thanks for the answer. I suppose I need to change my blocking scheme. Another error I get is with regard to symmetry boundaries. Although my planes are clearly defined. In ANSYS solver the solution is aborted with the following message:

The symmetry boundary condition requires that the boundary patch |
| mesh faces form a plane or axis. However, face set 4 in the |
| symmetry boundary patch| is not in a strict plane, which means that at least one of its |
| faces is not parallel to the others

I don't know what's going on. I've checked my boundary planes many times. Any ideas? Many thanks.

The error means you have elements of that face off the plane, so keep checking to find them.