极低比转速叶轮内流体的流动分析和叶轮的设计

通过分析得出影响低比转速离心泵效率的主要原因是在叶轮出口存在二次流、边界层的分离等而引起的射流一尾迹结构并提出了改进的方法。实例表明文中提出的加大叶轮出口宽度，采用较大的叶片出口安放角，较大的叶片包角和叶片的线型前部采用较小曲率半径，后部分采用较大的曲率半径等叶轮设计方法能够设计出具有较高效率和较好性能的低比转速离心泵。

Flow Analysis of the Impeller in Centrifugal Pump with Very Low Specific Speed

The reason affected on efficiency of centrifugal pump with very low specific speed is discussed. It is shown by analysis that the second flow, boundary layer separation, and the jet-wake structure near the impeller outlet is the important reason effected on efficiency of centrifugal pump with very low specific speed and it ,s improvement method is presented. The theory analysis and engineering application shows that centrifugal pump of very low specific speed with higher efficiency and better performance can be designed and produced if big impeller outlet width, big blade outlet angle, big blade warp angle redius are to be adopted and the former in blade shape is small curvature radius, the later is big curvature radius.