nagative volume
 

Hi dears...
What does it mean when we have negative volume in mesh?
how it happens?
thanx...

hi Dear
 

Negative volumes are normally reported when your geometry contains very small "loops"(the first cell of the boundary layer extends beyond the edge of your geometry)near the curved edges. You can check the following link.
http://www.cfd-online.com/Forums/flu...lume-mesh.html

Negative volumes occurs in the mesh because of the improper aspect ratio of the elements. It becomes a serious issue once if you try to deform the mesh. You can eliminate these negative volumes by using grid utility application that comes with your gird generator package.

You may also get negative volumes also if you have left-handed cells. E.g., in a 2D unstructured grid, when the mesher expect cell nodes indices numbered i-j-k-l in a counterclockwise direction, and you input some cells in clockwise direction.