诱导轮叶片数对超高速泵性能影响的研究

针对航空航天领域的一台超高速泵(38 500r/min),基于SIMPLEC算法,采用雷诺时均Navier-Stokes方程和RNGk-ε湍流模型,对带诱导轮和不带诱导轮两种结构下的流动进行三维湍流数值模拟,分析其在各工况下的内、外特性,就诱导轮叶片数对超高速泵性能的影响进行探讨。结果表明,添加诱导轮可以改善泵的性能及流动状态;Z3时,增加叶片数可改善诱导轮内的流动状态,提升诱导轮的水力性能,提高叶轮的汽蚀能力,使泵的整体性能逐渐上升;而当叶片数继续增加,泵的扬程虽然继续上升,但功率增大,效率下降,叶轮的汽蚀性能逐渐下降。诱导轮叶片数为3枚时,诱导轮内流动情况最优。Z=2时泵的整体性能最好。

Study on the Effect of the Number of Inducer Blades on the Performance of Super High-speed Pump

Aiming at a super high-speed pump (38500 r/min)in the aerospace field,based on the SIM-PLEC algorithm,using Reynolds averaging Navier-Stokes equations and RNG k-εturbulence model,numer-ical simulations of three dimensional turbulent flow were carried out for the flows under two kinds of structures with inducer and without inducer,the internal and external characteristics of the pump under va-rious operating conditions were analyzed,and the influence of the number of inducer blades on the perform-ance of super high-speed pump was discussed.The results showed that the performance and flow state of the pump could be improved by adding inducer;when Z <3,the increase of the number of blades could im-prove the flow state of the inducer,improve the hydraulic performance of the inducer,and improve the cavi-tation performance of the impeller,so that the overall performance of the pump gradually increased;howev-er,when the number of blades continued to increase,the lift of the pump continued to rise,but the power increased,the efficiency decreased,and the cavitation performance of the impeller decreased gradually.When the number of inducer blades was three,the internal flow conditions of the inducer were optimal.When Z =2,the performance of the pump was the best.