Numerical Simulation And Optimization Design On Internal Flow Of Centrifugal Pump

With the increasing of application and the shortage of energy, the optimization design of centrifugal pump becomes more and more important. Currently, the optimization design of centrifugal pumps are mostly single-objective, in which many methods have its own drawbacks, and not take into account the overall performance of centrifugal pumps. A multi-objective optimization method for the overall performance of centrifugal pumps is put forward in the help of the Matlab genetic algorithm toolbox, in which the optimization goal was based on efficiency, cavitation performance and stability, the main geometric parameters that affect the performance of centrifugal pumps are design variables, and considering the matching of centrifugal pump impeller and volute.The paper expounds the research situation and the development trend of CFD technology and the optimization design of centrifugal pumps.Taking the best matching relation between the impeller and volute into consideration, objective functions were was established, in which energy loss, net positive suction head and stability are dependent variables, and the main geometric parameters that affect the performance of centrifugal pumps, such as D2、β2、b2、D1、β1、b1、z、Y,are design variables.The weight factors of objective function were determined according to the importance of performance index. The objective functions were unified with the weighted linear method. The boundary conditions were confirmed according to empirical formulas and the production requirements of enterprises, and the optimization design is carried out in the help of Matlab genetic algorithm toolbox.Anew hydraulic model of centrifugal pump is established according to the optimization results. A three-dimensional model of centrifugal pump in fluid region both before and after optimization was plotted in the UG. The Gambit was adopted to mesh for the fluid region, and which is simulated in the Fluent. The fluid region both before and after optimization was analysed, finding that the pressure value of blade inlet after optimization in the area of low pressure is greater than before optimization, the relative speed streamline distribution in theflow channel is more reasonable than before optimization, and the vortex of volute at the exitis smaller.The results optimization was analysed between before and after. The results reveal thatthe efficiency of centrifugal pump is higher5.03%than before optimization, head of deliveryis lower0.67m, and the curve of head of delivery is flatter, the stability of which is better,demonstrating that the optimization method and numerical simulation is correct and effective.