Freeware CFD codes?

[ta5ari]

I am about to design a centrifugal pump and I wonder if there is available some freeware code to get some rough impeller sizing before buying a commercial code.
Any hints?
What are the best commercial codes for the purpose?

 

[BigInch]

Open Source Codes

NaSt3DGP

http://wissrech.iam.uni-bonn.de/research/projects/cfd/

OpenFoam

http://www.opencfd.co.uk/openfoam/index.html#openfoam

OpenFlower

http://openflower.sourceforge.net/whatis.html

Commercial Code

Fluent

http://www.fluent.com/

http://virtualpipeline.spaces.msn.com

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