Effect of balance holes and back blades on axial thrust of centrifugal pump
LIU Zailun1,2, LU Weiqiang2*, ZHAO Weiguo1,2, CHEN Taoli1
1. College of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou, Gansu 730050 China; 2. Engineering Institute of Wenzhou Pump & Value, Lanzhou University of Technology, Wenzhou, Zhejiang 325105, China
Abstract:In order to investigate the effect of balance holes and back blades on axial thrust of the low specific speed centrifugal pumps, the IS80-50-315 centrifugal pump was chosen as the research object. Four different projects were tested and numerically analyzed, which included the balance hole, the back blade and both of them and neither of them. The results show that the influence of the back blades on the hydraulic performance of the centrifugal pump is greater than that of the balance hole, and it plays a leading role in energy loss of centrifugal pump. Under the rated operating mode, the fluid pressure in front pump chamber radially changes with ladder shape, the fluid pressure in the rear pump chamber approximately linearly increases, and the fluid pressure in balance cavity almost shows linear distribution with the change of flow. In the same test pump, the balance hole has greater influence on the liquid pressure in the front pump cavity and the balance cavity. The back vane has a better effect on the pressure drop of fluid in the back-pump cavity. At the same time, the torque is obviously increased when back blades are added on the runner, but the torque of the runner is slightly increased with only balance holes. The balance hole has better balance effect on axial force than back blades under the full flow conditions, and the ability of balancing axial force is the worst when both of them exist.〓
刘在伦,,芦维强*,赵伟国,,陈淘利. 离心泵平衡孔和背叶片对轴向力特性影响[J]. 排灌机械工程学报, 2019, 37(10): 834-840.
LIU Zailun,, LU Weiqiang*, ZHAO Weiguo,, CHEN Taoli. Effect of balance holes and back blades on axial thrust of centrifugal pump. Journal of Drainage and Irrigation Machinery Engin, 2019, 37(10): 834-840.
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