中低比转速带导叶离心泵出水边倾斜角对无叶区压力脉动的影响研究

Research on the Influence of the Inclination Angle of Impeller Outlet Edge of the Centrifugal Pump with Guide Vanes at Medium and Low Specific Speed on the Pressure Fluctuation in the Vaneless Region

为研究中低比速带导叶离心泵叶片出水边倾斜角对叶轮和导叶干涉作用而引起的压力脉动的影响,在保证叶轮基本参数和叶片进出口安放角变化规律不变的情况下,通过改变叶片出水边倾斜角而设计2种计算方案。基于RNG k-ε湍流模型、SIMPLEC算法和无滑移网格技术,分别对2种叶片出口边倾斜角的叶轮的离心泵进行全流道非稳态数值计算,得到不同叶片出口倾斜角的叶轮无叶区压力脉动特性,并对其进行分析,计算结果表明叶片出水边倾斜角对无叶区压力脉动影响明显。本文对大型带导叶离心泵叶片水力设计提供一定的指导意义。

In order to study the influence of the inclination angle of the impeller outlet edge of the centrifugal pump blade with guide vanes at medium and low specific speed on the pressure fluctuation caused by the interference between the impeller and the guide blades, two schemes are designed by changing the inclination angle of outlet edge of the impeller, which is under the condition that the basic parameters of the impeller and the distribution rules of the angle of the inlet and outlet of the blades remain unchanged. Based on the RNG k-ε turbulence model, the SIMPLEC algorithm and the non sliding grid technology, the transient calculation of the whole flow passage of the centrifugal pump with the same guide vane matched by the impellers with different blade outlet inclination angles is carried out, and the pressure fluctuation characteristics of the centrifugal pump with different blade outlet inclination angles are obtained. The results show that the slope angle of the blade outlet has a significant effect on the pressure fluctuation in the vaneless zone. This paper provides some guidance for the hydraulic design of large centrifugal pump blades with guide vanes.