Numerical Analysis Of Centrifugal Pump And Optimization Research Of The Volute

Pumps belong to fluid machines and play a magnificent role in the transportation of fluid working medium. Since centrifugal pumps possess a great deal of advantages like high rotate speed, small size, simple structure, stable performance, convenient operation, they are widely used in power station, petroleum, chemical industry, and many other fields like agricultural irrigation, drainage and so on. However, pumps work with power-consuming process and low efficiency generally. Therefore, designing pumps independently is of great importance for the industrial development and power saving. The suction volute is an indispensable part of a centrifugal pump. The energy losses definitely exist in the volute because of the presence of viscosity. In addition, the internal flows in the volute directly affect the pressure and velocity distribution around the impeller which may influence the reliability of the impeller operation. As a result, the design of volute should not be treated slightly because of its enormous impact on the whole properties and efficiency index.The thesis focused on a residual heat removal pump model which was developed by a company. Based on the fluid dynamics theory, this paper analyzed the centrifugal pump overall performance. Through the usage of Pro/Engineer and IGG, the author established a three-dimensional model and generated mesh for the entire flow of centrifugal pump including the impeller, guide vane and volute. Finally, the internal flow field of the whole system was simulated by means of FINE software so that the flow characteristics inside the centrifugal pump were carefully analyzed.It can be concluded that the poor performance resulted from the improper design of volute. The author offered several proposals about optimum design and then checked them through numerical simulations in various work conditions and remarkably, the efficiency of the centrifugal pump was successfully increased by7%. This research also showed different patterns and sizes of cross section of the volute have some influences on the performance of centrifugal pumps. Peripheral uniformity in non-axisymmetric volute was better than that in the axisymmetric one. An optimum relative position exists between the diffusion vanes and the volute.The research results presented in this paper may provide some guidelines for flow analysis and structure modifications of the volute. This method laid the foundation for the future design and manufacture of centrifugal pumps, which is much instructive and economical.