导叶数对多级离心泵反转式透平性能的影响

The Influence of Number of Guide Vanes on Performance of Inverted Turbine of Multistage Centrifugal Pumps

为研究导叶数对多级离心泵反转式液力透平性能的影响,以多级离心泵反转式液力透平首级为研究对象,设计了3种叶片数的导叶及相匹配的环形蜗壳。利用CFX软件进行定常及非定常数值计算,获得模型泵工况、透平工况的外特性曲线和内流场分布,以及导叶、蜗壳的内部压力脉动数据,并进行分析。结果表明:导叶数越少的模型内部流动越均匀。7片导叶数模型的回收功率及效率均为最大,但导叶数越少的情况下,导叶及蜗壳处的压力脉动幅值也越大。当导叶叶片数大于等于9片时,模型内部的压力脉动幅值基本保持不变。

In order to study the influence of the number of guide vanes on the performance of the inverted hydraulic turbine of multistage centrifugal pumps,in this paper,the first stage of multistage centrifugal pump inverted hydraulic turbine is taken as the research object,and3 kinds of vane guide vanes and annular spiral casing matching each other are designed. CFX software is used in steady and unsteady numerical calculations. The outer characteristic curve and the internal flow field distribution of the model pump and turbine condition are obtained,and the internal pressure pulsation data of the guide vane and volute are analyzed. The results show that： the smaller the number of guide vanes,the more uniform the flow inside the model. The power and efficiency of the 7 vane models are the largest,but the less the number of guide vanes,the greater the pressure fluctuation amplitude at the guide vane and volute. When the blade number is more than or equal to 9,the amplitude of the pressure fluctuation in the model remains almost unchanged.