低比转速泵圆柱形叶片型线的研究

Research of Molded Line for Cylindrical Blade of Low Speed centrifugal pump

根据叶片进出口边界条件,提出用三次多项式构造叶片型线的极坐标表达式,并导出了保证叶片安放角单调变化的叶片包角取值范围。该叶片型线的主要特点是其包角可作为设计常量由设计人员根据需要事先在一定范围内给定,并且随着叶片半径的增大,叶片曲率半径单调增长,叶片安放角单调均匀变化,从而减少了叶片表面的脱流损失,提高了离心泵的水力效率。

Based on the boundary conditions at blade inlet and outlet,the cubic polynomial is used to construct the expression of blade-type in polar coordinates;and the range of blade wrap angle which ensures that the vane setting angle varied monotonously is deduced.The main feature of this blade-type is that the wrapping angle is used as a designing constant,which can be preseted within a certain range.With the increase of blade radius,the blade radius of curvature increases monotonously,the vane setting angle changes monotonously and evenly.Thus the loss of off-flow on the surface of the blade is reduced and the efficiency of centrifugal pump is raised.