We have developed a coherent set of techniques for parallel computing. We have used the Finite Element Method associated with the C++ Object-Oriented Programming with only one database. A technique of data selection is used in the determination of the data dedicated to each processor. This method is performed by SIMD technology associated with MPI capabilities. This parallel computing is applied to very large CPU cost problems particularly the unsteady problems or steady problems using iterative methods. Different results in Computational Fluid Dynamics are presented.