Abstract：A comparative study was conducted between two types of cut-water shapes which significantly affect the performance of a centrifugal pump to improve the accuracy of performance prediction and reduce development costs for the pump. The computational fluid domains include suction pipe, impeller and volute, which were meshed with Ansys ICEM CFD code to generate a structured mesh and the numerical simulation of flow in the pump was accomplished with Ansys CFX. There is the normal velocity boundary condition at the inlet to the suction pipe, and there exists the outlet pressure condition at the discharge of the volute diffuser. The mechanical and volumetric efficiencies were considered to be 89% and 96%, respectively. It was found that the simulated performance for the pump with round cut-water shape is close to the test data at various flow rates. The simulated performance for the pump with rectangular cut-water shape is near the measured result at low flow rates, but shows a relatively noticed difference from the measured one at a high flow rate. According to the pressure contours and streamline plots, the high pressure zone on the round cut-water is relatively stable and the streamlines around it are smooth with increasing flow rate. For the rectangular cut-water shape, however, the high pressure zone is unstable to shed a series of vortices at the design condition and high flow rate. Those vortices alter flow patterns in the volute and eventually result in that the predicted performance differs from the measurement considerably. The reason, why there is a significant difference in the perfor-mance exists between two types of cut-water shapes, has been clarified by analyzing the flow field in the volute. It is confirmed that a round cut-water can make flow pattern in the volute smoother and subsequently improves the pump performance.
袁寿其, 衡亚光, 洪锋, 袁建平, 司乔瑞, 胡博. 2种隔舌模型对离心泵性能模拟的影响[J]. 排灌机械工程学报, 2013, 31(7): 553-557.
Yuan Shouqi, Heng Yaguang, Hong Feng, Yuan Jianping, Si Qiaorui, Hu Bo. Influence of two types of cut-water shapes on simulated performance of centrifugal pump. Journal of Drainage and Irrigation Machinery Engin, 2013, 31(7): 553-557.
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