低比速多级潜水泵优化设计

按无过载设计要求,为大幅度提高效率,以QS10低比速潜水泵的优化为例,选择叶轮出口宽度、叶片进口冲角、叶轮叶片数、导叶进口安放角等10个参数为变化因素,按L27(310)正交试验方案设计了27组模型;研究了适合多级泵性能预测的方法;通过分析计算流体力学两级全流场数值模拟的结果,得到各几何参数对轴功率、效率指标影响的主次顺序:导叶叶片进口安放角β3对效率的影响最大,叶片出口安放角β2对轴功率的影响起主要作用;将正交分析所得到的最优方案制成样机进行性能测试,该优化模型泵额定点效率为58.61%(大于国家规定的效率值51%),最大轴功率值为3.83 kW(符合设计要求的4 kW),验证了正交设计结合数值模拟手段在泵优化设计方面的可行性。

Optimal design of submersible multistage pumps with low specific speed

In order to satisfy the demand of non-overload, submersible pump QS10 was selected as example to improve efficiency of centrifugal pump with low-specific-speed. Ten factors were carefully designed such as outlet width of impeller blade, inlet attack angle, blade number, inlet setting angle of guide vane, etc. 27 projects were decided upon L27(310)orthogonal test and the method of predicting multi-stage pump performance was studied. Based on analyzing the numerical simulation results of 2 stage models, the influence orders of geometry parameters on pump shaft power and efficiency were obtained. Results show that inlet setting angle of guide vane is predominant of ten factors affecting efficiency while blade setting angle is predominant affecting shaft power. And the optimal project selected after orthogonal test analysis was produced to test. The efficiency of designed point is up to 58.61% higher than the state regulation 51% and the maximum shaft power value is 3.83 kW complying with the design requirement of 4 kW, which verified the feasibility of the method of orthogonal design combined with numerical simulation in pump optimization design.