CFD (Computational Fluid Dynamics) is a numerical calculation method to analyze all kinds of flow phenomenon by solving 3D flow control equations. With the development of CFD and computer technology, it is now possible to analyze the internal flow field and predict the performance of hydraulic machinery. The flow field analysis and external performance prediction of hydraulic machinery using CFD has the advantages of cheap, fast, accurate etc. Therefore, the research and development (R&D) cost and cycle are greatly reduced using CFD. Our company could numerically analyze the flow field and predict the external performance of all kinds of hydraulic machinery, according to customer demands.