CFD (Computational Fluid Dynamics) and related NHT (Numerical Heat Transfer), the theory of Computational Combustion is to numerically solve the differential equations of nonlinear mass, energy, component, momentum and custom scalar. The results can predict the details of the process of flow, heat transfer, mass transfer, and combustion and become a powerful tool for process optimization and amplification. The basic characteristics of CFD are numerical simulation and computer experiments. From the basic physics theorem, it has replaced costly fluid dynamics experimental equipments to a large extent and has hug influence in scientific research and engineering technology. It Is a quite important research fields in the world, the core and important technology of heat transfer, mass transfer, momentum transfer and combustion, multiphase flow and chemical reaction. It is widely used in aerospace design, automobile design, biomedical industry, chemical processing industry, turbine design, semiconductor design, HAVC & R and many other engineering fields. Plate fin heat exchanger design is one of the most important fields of CFD technology applications.