Computational Fluid Mechanics (CFD) is one of the most widespread branches of numerical simulation. The purpose of CFD is to numerically solve the equations that govern the behavior of fluids, the Navier Stokes equations, which have no analytical solution. The evolution of the CFD has been such that now a days it allows to simulate a multitude of phenomena related to fluid mechanics: multiphase flows, turbulence, mass and energy transfer, transport and reaction of chemical compounds in a fluid, etc.