轴流式喷水推进泵的三元设计

Three-dimensional inverse design method applied to waterjet axial-flow pump

运用泵的三元设计理论和计算流体力学（CFD）数值计算方法对大功率、高效率轴流式喷水推进泵进行水力设计和性能预报，并对喷口轴向长度、叶轮叶片随边与导叶叶片导边的轴向距离以及叶顶间隙对喷泵水力性能的影响进行进一步计算与分析。从理论上说明叶轮叶片和导叶叶片之间存在最佳匹配距离，该最佳间距为标称直径的3%~4%。运用黏性雷诺时均方法（RANS）对所设计轴流式喷泵水力性能进行数值预报。研究结果表明：泵在设计流量点效率达到92.3%，同时也满足抗空化性能要求，且在较宽的流量范围内具有良好的水力性能。

A large power and high efficiency axial-flow waterjet pump was designed by the three-dimensional inverse design method, whose performance was predicted by CFD. The influences of the length of nozzle, the axial distance between a rotor’s trailing edge and a stator’s leading edge, and the clearance of rotor blade tip on pump’s hydraulic performance, were studied in the design process. The results show that there must be an optimized distance in theory and the best one in this example is 3%-4% of the pump’s inlet diameter. The result of this research provides a reference for the waterjet pump designers. Then, the performance of the axial-pump is calculated using RANS simulation, which indicates the pump has good cavitation and high efficiency with 92.3% at the design point.