中文摘要：

通过分析变角调节前后水泵进出口速度三角形的变化关系，结合水泵内部水流运动的特性，推导出流量、扬程随叶片安放角变化的变角相似关系式，提出了以试验性能为依据，水泵变角相似关系式计算结果与试验数据之间的误差平方和最小为目标函数，通过数值逼近求解相似关系式流量指数和扬程指数的方法。针对南水北调水泵同台试验中的3种模型，分别求得水泵的变角相似关系，利用变角相似关系式计算的结果与试验数据间的误差分别为2．28％、1．16％、1．23％，流量一扬程曲线计算结果与试验数据之间吻合很好，流量一功率曲线计算结果与试验数据基本吻合。水泵变角相似关系式可用于此类水泵变角度的性能换算，具有较好的相似性。

英文摘要：

First this paper analyzes the change of velocity triangles at the inlet and outlet of a pump impeller caused by blade adjusting, examines the flow behaviors in the pump passage, and derives pump blade adjusting formulae that reflect the variations of flow and pumping head with blade adjusting. And then we develop a mathematical model for calculation of the flow index and head index of these formulae based on the experimental data of pump performances, and formulate an objective function that is the least square sum of the formulae＇s calculation errors relative to the test data. Application of the formulae to three model pumps shows that the percentage errors are 2, 28% , 1.16% and 1.23% respectively, and that all the flow-head curves and flow-power curves agree well with the test curves. Thus, the derived formulae that are featured with good similarity, are applicable to performance conversion of pump blade adjusting.