文丘里型进口段参数对高速泵流动特性影响

The Influence of Parameters of Inlet Section with Venturi Tube Shape on Flow Characteristics of High-Speed Pumps

为研究文丘里型进口段参数对于高速离心泵流动特性及水力性能的影响,选择圆弧段半径r、直线段长度L以及进口段最小内径D 3个进口段参数,每个参数取3个水平,正交组合确定模型方案。采用ANSYS-CFX软件进行三维流场模拟,对比分析了小流量工况下各参数对泵体效率及扬程的影响、进口段流场分布情况以及多流量工况下效率、扬程曲线的变化。结果表明:进口段最小内径D对于高速泵流动特性影响较大;文丘里型进口段在小流量工况下能有效抑制诱导轮入口处回流的扩散,在一定程度上提高水力性能,但同时会加剧进口段内部旋涡的产生。

The influence of the parameters of Venturi inlet on the flow characteristics and hydraulic performance of high-speed centrifugal pump is studied.The parameters of arc radius r,linear length L and minimum inner diameter D of the inlet are selected.Each parameter is taken at three levels,and the model scheme is determined by orthogonal combination.ANSYS-CFX software is used to simulate the three-dimensional flow field.The effects of parameters on pump efficiency and head,the flow field distribution in the inlet section and the change of efficiency and head curve under multi-flow condition are compared and analyzed.The results show that the minimum inner diameter D of the inlet section has a great influence on the flow characteristics of high-speed pumps.Venturi-type inlet section can effectively restrain the diffusion of backflow at the inlet of induction wheel under the condition of small flow rate,and improve the hydraulic performance to a certain extent,but at the same time intensify the generation of internal vortices in the inlet section.