基于正交试验的高压应急提水泵优化设计

Optimal design of high-pressure emergency water pump based on orthogonal test

为了提高高压应急提水泵的水力性能,分析叶轮几何参数对泵效率的影响顺序,对BB4型多级离心泵首级叶轮和次级叶轮分别进行正交试验设计.首级叶轮需考虑抗汽蚀性能,故选取叶片前盖板流线进口安放角、中间流线进口安放角、后盖板流线进出口安放角、叶轮进口直径、叶轮外径和叶片包角等7个几何参数作为设计因素.次级叶轮选取叶轮前盖板流线进出口安放角、中间流线进出口安放角、后盖板流线进出口安放角和叶片包角等7个因素,每个因素取3个水平,共设计18组方案.采用STAR-CCM+软件对单级叶轮进行数值模拟,分析了叶轮内流场变化,并通过极差分析得到各几何参数对叶轮效率的影响显著.将优化后首级叶轮和次级叶轮替换成三级泵模型初始叶轮,通过数值模拟得到优化后多级泵外特性参数.结果表明:在一定范围内适当增大包角和叶片进口安放角、减小叶轮外径能提升叶轮效率,改善叶轮抗汽蚀性能;在叶轮基本尺寸不变时,适当减小叶轮进口安放角,增大包角能提高叶轮效率;分析对比优化前后外特性参数,验证了正交试验设计方法结合数值模拟能对高压应急提水泵进行优化设计.

In order to improve the hydraulic performance of high-pressure emergency water pump,and analyze the order of influence of impeller geometric parameters on pump efficiency,an orthogonal 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 must 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 and 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 took 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 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.