Optimization design of low specific speed shield pump based on orthogonal experiment

Abstract

Abstract Low specific speed pump is characterized by generally low efficiency, easy to appear hump and optimization difficulties. In order to improve the hydraulic performance of the pump at the shut-off point (0.2Q d) and reduce the hump phenomenon, the influence of impeller geometric parameters on the hydraulic performance of the pump is analyzed without changing the volute structure, the orthogonal experimental design of impeller parameters is carried out. Six geometric parameters, including impeller outlet diameter, impeller outlet width, blade inlet angle, blade outlet angle, wrap angle and blade thickness, are selected as design factors. Each parameter factor is taken to 3 levels, and a total of 18 schemes are designed. 3D impeller design is carried out based on CFturbo, numerical simulation is carried out with CFX. The results show that increasing the impeller outlet diameter can increase the head within a certain range. The impeller efficiency can be improved by reducing the outlet width of the impeller, increasing the blade inlet angle and increasing the wrap angle. The pump performance parameters before and after optimization are analyzed and compared, it is verified that the orthogonal experimental design method combined with numerical simulation can optimize the design of low specific speed shield pump.