OpenFOAM CFD (Open Field Operation and Manipulation, Computational Fluid Dynamics) is an open source software extensively used to get fluid problem solutions through their specialized libraries. The complete C++ modules run in a Linux operating system basis.
ParaView (Parallel Visualization Application) is a computer tool which can run under Windows OS. This tool has been designed to visualize data sets either small or very large.
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ParaView visualization example of an OpenFOAM tutorial case data