Abstract：In order to analyse influence of impeller trim on performance of a multistage centrifuge pump with radial diffuser and volute and identify differences in the performance resulted from impeller trim in single-stage and two-stage cases, 3D turbulence flows through the second and third stages of MD-280-43×6 multistage centrifugal pump are simulated numerically by solving the Navier-Strokes equations and standard k-ε turbulence model based on SIMPLE algorithm. The results show that in the single-stage case the hydraulic efficiency of the pump model decreases more obviously when the impeller is trimmed in the volute than that when the impeller is trimmed in the radial diffuser. In particular, the hydraulic loss is increased by 0.360 m, 0.193 m in the volute and diffuser in average, respectively, for each 2% impeller trim. The fluid dynamic pressure distribution and the change in radial thrust caused from impeller trim are quite different from the diffuser to the volute. In the two-stage case, the hydraulic efficiency, head, turbulent kinetic energy are changed by 1.644%, 2.090 m and 1.302 J/kg in average due to impeller trim, compared with 0.279%, 1.573 m and 1.548 J/kg in the single-stage case. Therefore, the difference in performance caused from diffuser and volute should be taken into account when an impeller is trimmed in a multistage centrifugal pump. Also, the performance prediction for trimmed impellers should be based on two or more stage model rather than single-stage one.
杨从新, 富友, 强盼, 刘洋. 不同压出室下叶轮切割对离心泵性能影响[J]. 排灌机械工程学报, 2015, 33(9): 750-755.
Yang Congxin, Fu You, Qiang Pan, Liu Yang. Influence of trimmed impeller on performance of a multistage centrifuge pump with radial diffuser and volute. Journal of Drainage and Irrigation Machinery Engin, 2015, 33(9): 750-755.
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