Abstract:To study the different behavior of a double suction centrifugal pump when it is running as a pump and a turbine, the standard k-ε two-equation turbulence model and CFX software are used to simulate the internal flow filed in pump and turbine modes and their performances are predicted. The hydraulic performances at best efficiency points are calculated respectively in pump and turbine modes, and a comparison of the flow field is made as well. The predicted performance curves in the pump mode are compared with the experimental values, showing the numerical simulation can predict the performance curves accurately. When the pump running as a turbine, the best efficiency point is moved to a larger flow rate and the efficiency varied greatly across the whole range of flow rate. A too small flow leads the torque acted on the impeller by the fluid to the reversed direction and stops doing work on the impeller. Moreover the largest energy loss occurs in the vaneless region between the impeller and volute, namely the outlet of the impeller. Through an analysis of the internal flow field in pump mode, the detailed distributions of pressure and velocity vector are obtained, and these results can provide a useful base on the hydraulic design of a pump as turbine.
王春林, 曾成, 杨晓勇, 彭海菠, 刘栋. 双吸泵正反转内部流场数值模拟及性能预测[J]. 排灌机械工程学报, 2015, 33(7): 577-582.
Wang Chunlin, Zeng Cheng, Yang Xiaoyong, Peng Haibo, Liu Dong. Numerical simulation of internal flow field and performance prediction of reversible double suction pump. Journal of Drainage and Irrigation Machinery Engin, 2015, 33(7): 577-582.
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