OpenFOAM is a free, open source CFD software.
GT-SUITE is a versatile multi-physics platform for constructing models of general systems.
Fire Dynamics Simulator (FDS) is a computational fluid dynamics (CFD) model of fire-driven fluid flow. The software solves numerically a form of the Navier-Stokes equations appropriate for low-speed, thermally-driven flow, with an emphasis on smoke and heat transport from fires.
[SPECIAL LICENSE REQUIRED: contact hpc-support@umich.edu] CONVERGE is a CFD code with adaptive meshing.
ANSYS is a finite element simulation tool for multiphysics simulations.