叶片进口边位置对单叶片离心泵性能的影响

Influence of blade inlet edge position on performance of single-blade centrifugal pump

为研究叶片进口边位置对单叶片离心泵性能和内部流动特性的影响,设计了6种不同叶片进口边位置的叶轮.在完成数值计算方法可靠性的试验验证后,分别对采用6种叶轮的泵进行了全流场定常数值计算.计算结果表明:叶片进口边沿前盖板或后盖板向泵入口适当延伸,可增强叶片对流体的控制能力和叶片的做功能力,扬程最大可分别提高1.61 m和0.70 m,效率最大可分别提高5.23%和2.01%;叶片进口边向泵入口延伸过多,会造成叶片入口处流体堵塞,某些工况下泵的扬程和效率反而会降低;叶片进口边沿前盖板或后盖板向泵入口延伸,可降低流体在叶片入口处的能量损失,能够提高叶片吸力面入口处的压力,和减小蜗壳内的低速区域,但是会增大叶片入口处、叶片压力面前端和叶片吸力面附近的低速区域.与叶片进口边沿后盖板向泵入口延伸相比,叶片进口边沿前盖板向泵入口延伸对泵的扬程和效率影响更明显.

In order to study the influence of blade inlet edge position on the performance and internal flow characteristics of single blade centrifugal pump,six impellers with different blade inlet edge position were designed.The numerical calculation results were verified with the experimental results,and the steady numerical calculation of the whole flow field of the pump with six kinds of impellers was carried out.The calculation results show that the proper extension of the shroud or hub along the blade inlet edge to the pump inlet can enhance the fluid control ability and work ability of the blade.The maximum head increases by 1.61 m and 0.70 m respectively,and the maximum efficiency increases by 5.23%and 2.01%respectively.If the blade inlet edge extends too much to the pump inlet,the fluid at the blade inlet will be blocked,and the pump head and efficiency will be reduced under some working conditions.The blade inlet edge extends to the pump inlet,which can reduce the energy loss of fluid at the blade inlet.It can also increase the pressure at the inlet of the blade suction surface and reduce the low-speed area in the volute.However,it will increase the low-speed area at the blade inlet,the front end of blade pressure and near the blade suction surface.Compared with the extension of the blade inlet edge along the hub to the pump inlet,the extension of the blade inlet edge along the shroud to the pump inlet has a more obvious impact on the pump head and efficiency.