Gmsh - Gmsh is a 3D finite element grid generator with a build-in CAD engine and post-processor.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
FreeCAD - An open-source parametric 3D modeler
TetGen - A Quality Tetrahedral Mesh Generator and a 3D Delaunay Triangulator
MATLAB - A high-level language and interactive environment for numerical computation, visualization, and programming
Paraview - ParaView is an open-source, multi-platform application designed to visualize data sets of size...