Optimization of a Sewage Pump Based on CFD Analysis

In this paper, the internal steady solid-liquid two-phase flow inside a sewage pump was numerically calculated by using the "frozen rotor method" and Mixture model. The hydraulic performance and wear characteristics of flow components were emphatically compared and analyzed for the pump with two kinds of diffusion structures and three kinds of blade outlet angles. Research results show that for the curving diffusion and the straight diffusion structure, there is no significant impact on the external performance of the pump. The calculated head and efficiency of the pump with the curving diffusion are slightly higher than that of the straight diffusion pump, but the difference between them is very limited. Comparatively, the wall wear is slighter when the sewage pump is with the straight diffusion. With the increase of blade outlet angle, the pump heads show an increasing trend, while the impact on the efficiency curve is not significant. The research manifest that the pump model with blade outlet angle of 30 ° and straight diffusion has relatively good hydraulic performance and wear properties.