Cubit

CUBIT is a full-featured software toolkit for robust generation of two- and three-dimensional finite element meshes (grids) and geometry preparation.

Its main goal is to reduce the time to generate meshes, particularly large hex meshes of complicated, interlocking assemblies. It is a solid-modeler-based preprocessor that meshes volumes and surfaces for finite element analysis. Mesh generation algorithms include:

-Quadrilateral and triangular paving
-2D and 3D mapping
-Hex sweeping and multi-sweeping
-Tet meshing
-Many special purpose primitives.