PIV test on hump phenomenon of low specific speed centrifugal pumps
Ma Haochen1, Ding Rong2, Yang Dongsheng3
1.School of Mechanical Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China; 2.Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang, Jiangsu 212013, China; 3.Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
Abstract：The hump in performance curve of low specific speed centrifugal pumps affects the reliability obviously, which is still not solved today. In order to study inner flow mechanism of the hump, two hydraulic models are designed according to the same design requirements, in which scheme 1 has hump phenomenon and scheme 2 has no hump phenomenon. The performance of the two models is tested to validate the design. Then the internal flow of two model pumps are tested and analyzed by particle image velocimetry(PIV)system. The results show when performance curve appears hump, low speed area at the pressure side of the impeller blade increases rapidly, and vortex appeared at blade pressure surface of several channels. In the gap between impeller outlet and volute base circle, the flow rate of recirculation increases. The velocity difference between the impeller outlet and base circle of the volute also increases significantly, which results in increase of the hydraulic loss in the pump and causes hump phenomenon of the performance curve. The research results of the study can provide theoretical references to control the hump phenomenon of low specific speed centrifugal pumps.
马皓晨, 丁荣, 杨东升. 低比转数离心泵驼峰现象的PIV测试[J]. 排灌机械工程学报, 2013, 31(12): 1056-1060.
Ma Haochen, Ding Rong, Yang Dongsheng. PIV test on hump phenomenon of low specific speed centrifugal pumps. Journal of Drainage and Irrigation Machinery Engin, 2013, 31(12): 1056-1060.
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