Blender - Blender is the open source, cross platform suite of tools for 3D creation.
SimFlow - SimFlow is a powerful CFD software, focused on engineering and science.
FreeCAD - An open-source parametric 3D modeler
entree - Entree
MATLAB - A high-level language and interactive environment for numerical computation, visualization, and programming
SimulationHub - Cloud-based CFD solution.