Optimization of a Centrifugal Pump Used as a Turbine Impeller By Means of an Orthogonal Test Approach

A prototype centrifugal pump with the specific speed of 110 is used to investigate the performance of turbine for power generation. A particular attention focuses on the design and optimization of the internal impeller. Internal flow field is simulated using a commercial CFD software and four geometrical parameters of the impeller, i.e., inlet diameter, inlet width, blade number and blade angle, are chosen as the designed variables. Each parameters are optimized within three levels, and the optimization is conducted based on the Orthogonal test method. The simulated results of the prototype turbine show good agreement with the experimental results under different flow conditions. According to the L934design table, the head and efficiency under the rated flow rate of the nine designed schemes are calculated. The calculation results are concluded through the method of range analysis to obtain the finally optimized model. This study enriches the design method of hydraulic turbine and provides reference for the design of centrifugal pump as the turbine.