CFD is the English acronym of “ Computational Fluid Dynamics ”, which can be translated into French by the phrase “ Numerical Mécanique of the Fluids ” (MFN). The MFN consists in studying the movements of a fluid, or their effects, by the numerical resolution of the equations governing the Fluide. According to the approximations chosen, which are in general the result of a compromise in term of needs for physical representation compared to the resources of calculation or modeling available, the solved equations can be the equations of Euler, Navier-Stokes equations, etc

The MFN grew of a mathematical curiosity to become an essential tool in practically all the branches of the dynamics of the fluids, of the weather propulsion Aérospatiale with the predictions S while passing by the drawing of the hulls of Bateau X.

In the field of research, this approach is the object of an significant effort, because it gives access to all instantaneous information (speed, pressure, concentration) for each point of the field of calculation, for generally moderate overall costs compared to the corresponding experiments.

In a general way, the resolution of a problem of MFN passes by three great phases:

1. preparation of the problem: this passes by the definition of a geometry, of a grid discretizing the field of calculation, of the choice of the models and numerical methods employees

2. the numerical resolution of the problem which passes by the execution of a computer program. Many problems causing a minimum of interest computers with the very great capacities require;
3. analysis of the results: the latter are checked in order to check their coherence, then examined in order to bring answers to the questions raised by the problem of starting MFN. This exploitation generally passes by software of scientific postprocessing used in many branches of physics, or by the modules of postprocessing available in certain software of commercial MFN.