中文摘要：

叶轮叶片数是离心叶轮的一个重要结构参数,对叶轮外特性与内流场特征都有着直接的影响。利用计算流体动力学软件,生成了叶片数分别为5和6的2个叶轮,然后在相同工况下,计算了这2个叶轮的内外力学性能;通过对2个叶轮的流量-扬程、流量-效率曲线及叶轮内压力、相对速度进行比较,分析了不同叶片数对叶轮性能产生的影响及其成因。比较分析结果有助于设计人员深入了解不同叶片数叶轮的不同流动机理,并可为他们在设计实践中正确选用叶片数提供参考。

英文摘要：

Blade number,as an important structural parameter for centrifugal pump impeller,directly affects both external performance of the impeller and internal flow field. We create two impellers with 5 and 6 blades respectively using CFD software,and analyze the internal and external mechanical property of the impellers under the same operating condition. Through the comparison of H ～ Q,η ～ Q characteristic curves,the internal pressure and relative velocity of the two impellers,the influence of different blade number on impeller performance and the causes are analyzed. The comparative and analytic results can help design professionals to deeply understand the flow mechanism of impellers with different blade number and correctly select the blade number in design.