Analysis of gas-liquid two-phase flow characteristics of mining multistage emergency drainage pump
CAO Weidong1,2, XU Yumin1*, ZHANG Hua2, WANG Xichen
1. National Research Center of Pumps, Jiangsu University, Zhenjiang, Jiangsu 212013, China;2. Nanjing Hegong Intelligent Environmental Protection Research Institute Co., Ltd., Nanjing, Jiangsu 211500, China;3. South to North Water Diversion East Line Jiangsu Water Source Co., Ltd., Nanjing, Jiangsu 210019, China
Abstract:In order to study the influence of gas-liquid two-phase flow on the performance of mining multistage emergency drainage pumps, a four-stage mining submersible centrifugal pump was taken as the research object, and the steady air and water turbulent flow fields in the four-stage pump with different air volume fractions and bubble diameters were numerically simulated with ANSYS CFX numerical simulation method based on the Eulerian-Eulerian multiphase flow model. The pump performance curves and rotor axial force were obtained, and the head, efficiency and axial force, as well as the air distribution features in this pump were analyzed and compared. The results show that under the condition of gas-liquid two-phase flow, the diameter of bubble particles and the air volume fraction have significant influence on the performance of the pump and the axial force of the rotor. In the case of large flow and high air volume fraction at the inlet, the head and efficiency of the mining multistage emergency drainage pump will drop sharply, and the direction of the residual axial force of the rotor is opposite to that of the residual axial force of the rotor under the normal operation condition. For internal flow field, there is local reflux at the impeller outlet when the pump runs under the condition of gas-liquid two-phase flow, and the reflux flows from the suction sides to the pressure sides in the impeller.