Optimal design of high-pressure emergency water pump based on orthogonal test
GUO Yongsheng1, CHEN Hongjun2, SI Qiaorui1, BAI Xiaobang2, WANG Peng1, YUAN Shouqi1*
1. National Research Center of Pumps, Jiangsu University, Zhenjiang, Jiangsu 212013, China; 2. Chongqing Pump Industry Co., Ltd., Chongqing 400033, China
Abstract:In order to improve the hydraulic performance of high-pressure emergency water pump, as well as analyzing the order of influence of impeller geometric parameters on pump efficiency, an ortho-gonal test design was carried out on the primary impeller and secondary impeller of a BB4 multi-stage centrifugal pump. The anti-cavitation performance of the first-stage impeller should be considered, for which seven geometric parameters that influence cavitation performance such as streamline inlet angle of the front cover plate, middle streamline inlet angle of the blade, rear cover plate inlet angle, outlet angle, impeller inlet diameter, impeller outer diameter, as well as the blade wrapping angle were used as design factors. For the secondary impeller, the following seven factors including the inlet and outlet angles of the impeller front cover plate streamline, inlet and outlet angles of the middle streamline, inlet and outlet angles of the rear cover plate as well as the blade wrapping angle were selected. Each factor takes 3 levels, and a total of 18 scheme groups were designed. The single-stage impeller was numerically simulated based on the Star-CCM software, the changes of flow field in the impeller were analyzed, and the influence order of geometric parameters on impeller efficiency was obtained through range analysis. Replace the optimized first-stage impeller and secondary impeller with the initial impeller of the three-stage pump model, and the hydraulic performance parameters of the optimized multi-stage pump were obtained through numerical simulation. The results show that increasing the wrapping angle and the blade inlet angle appropriately within a certain range, as well as reducing the outer dia-meter of the impeller can improve both the impeller efficiency and the cavitation resistance of the impeller. When the basic size of the impeller remains unchanged, appropriately reducing the placement angle of the impeller inlet, as well as increasing the wrapping angle can improve impeller efficiency. By analyzing and comparing the hydraulic performance parameters before and after optimization, it is verified that the orthogonal test design method combined with numerical simulation can optimize the high-pressure emergency water pump design economically and efficiently.