Analysis of the Unsteady Flow Characteristics of Chemical Centrifugal Pump as Turbine at the Best Efficiency Point Condition

doi:10.3901/JME.2021.22.395

Abstract

Abstract: Considering that the self-developed deep-sea electric pump operates under off-design conditions, its internal unsteady fluid radial force may cause vibration of the pump and even bring harm to the whole mining system. At present, it is impossible to calculate the radial force directly through theoretical formula. Therefore, the experimental and numerical simulation methods are used to study the regular and the production mechanism. Firstly, the accuracy of the numerical simulation method is verified by hydraulic performance test of the electric pump, and then the pressure distribution in the six-stage deep-sea electric pump and the radial force distribution of the fluid in the pump and its generating mechanism are studied. Finally, the radial force distribution law of two-stage deep-sea electric pump under different flow rates is compared and analyzed. The results show that the radial force in impeller at all stages varies periodically, and the stronger the regularity is at the last stage; the change period of radial force in impeller at all stages is related to the number of impeller blades. When other parameters remain unchanged, the smaller the flow rate is, the greater the radial force is, and the stronger the fluctuation is.

Key words: centrifugal pump, hydraulic turbine, optimal working condition, unsteady flow characteristics, numerical simulation

CLC Number:

TH311

LIN Tong, LI Xiaojun, ZHU Zuchao, XIE Huadong, HU Jianxin. Analysis of the Unsteady Flow Characteristics of Chemical Centrifugal Pump as Turbine at the Best Efficiency Point Condition[J]. Journal of Mechanical Engineering, 2021, 57(22): 395-405.

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