矿用多级抢险排水泵气液两相流动特性分析

为研究气液两相流对矿用多级抢险排水泵性能的影响,以一台四级矿用潜水离心泵为研究对象,采用 ANSYS CFX数值模拟方法,基于Eulerian-Eulerian多相流模型,对不同气体体积分数,不同气泡直径、四级离心泵进行气液两相流定常数值模拟.模拟得到气液两相流下的矿用多级抢险排水泵性能曲线及转子轴向力,并对扬程、效率、转子轴向力进行分析对比,同时分析泵内部气体分布规律.结果表明:在气液两相流条件下,气泡直径、气体体积分数都对泵的外特性及转子轴向力有显著的影响,在大流量、气体体积分数比较高的情况下,矿用多级抢险排水泵的扬程和效率会急剧下降,并出现转子残余轴向力与正常运行条件下转子残余轴向力方向相反的情况;内部流动中,气液两相流条件下叶轮出口出现局部回流,回流从吸力面流向压力面.

Analysis of gas-liquid two-phase flow characteristics of mining multistage emergency drainage pump

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.