Flowmaster  
   A 1D thermo-fluid systems package to simulate fluid systems behaviour. The site features a guided tour introducing the features of the software. It gives example applications and references.
   http://www.flowmaster.com

fluidyn  
   Software developed by Transoft International in the field of computational fluid dynamics, heat transfer, structural mechanics, environmental engineering and ground water pollution.
   http://www.fluidyn.com

Analytic & Computational Research, Inc  
   Has a general purpose CFD software suite (ANSWER) for reacting/non-reacting flows. Turbulence, structured or unstructured hybrid meshes can be handled.
   http://www.acricfd.com/software/answer/

PORFLOW  
   Enables groundwater engineers and nuclear waste management professionals model flows in porous media over extended periods of time.
   http://www.acricfd.com/software/porflow/

keyFE2  
   The site presents a finite element analysis software devoted to the calculation of flows. User defined equations may be added to the program.
   http://users.skynet.be/keyFE2/keyFE2.html