高速多级深井泵固液两相流及磨损特性

Solid-liquid two-phase flow and wear characteristics of high-speed multi-stage deep-well pumps

为研究高速多级深井泵内部固液两相流动以及过流部件的磨损特性,采用DPM离散相模型对深井泵内部流动进行数值模拟,并采用磨损模型对叶轮和空间导叶进行磨损数值计算,分析在不同流量下固相颗粒在深井泵内部的流动规律以及叶轮和空间导叶的磨损情况.研究结果表明:在小流量工况下,颗粒在叶轮叶片进口处轨迹较为紊乱,颗粒速度随着流量的增大而增大;颗粒主要分布于叶轮叶片的头部和工作面上,随着流量的增大,颗粒分布面积逐渐扩大;在空间导叶上,颗粒主要呈带状分布于叶片工作面靠近外缘处,且在大流量工况下,叶片上颗粒堆积现象较为严重;叶轮叶片的磨损区域随着流量的增大而扩大,磨损程度以叶片头部最为严重;空间导叶的磨损率和磨损区域随着流量的增大而增大,在大流量工况下叶片工作面靠近外缘处最为严重;第一级叶轮和空间导叶的最大磨损率最大,随着级数的增加,叶轮和空间导叶的最大磨损率逐渐减小;在第一级叶轮中小流量工况下的叶轮最大磨损率最大,额定流量工况下叶轮的最大磨损率最小;在第一级空间导叶中流量为6 m^(3)/h时最大磨损率分别为2 m^(3)/h和4 m^(3)/h的33.5倍和8.5倍;第一级空间导叶的最大磨损率受流量的影响较大.

In order to study the solid-liquid two-phase flow inside the high-speed multi-stage deep-well pump and the wear characteristics of the flow passage components,the discrete phase model(DPM)was used to numerically simulate the internal flow of deep-well pump,and the wear model was used to numerically calculate the wear of the impeller and space guide vane.The flow law of solid-phase particles inside the deep-well pump and the wear of the impeller and space guide vane under different flow rates were analyzed.The research results show that under the low flow rate condition,the trajectory of the particles at the inlet of the impeller blade is relatively disordered,and the particle velocity increases with the increase of flow rate.The particles are mainly distributed on the head and pressure surface of the impeller blade,and the particle distribution area gradually expands with the increase of flow rate.On the space guide vane,the particles are mainly distributed in a band on the pressure surface of the blade near the outer edge,and the particle accumulation on the blade is more serious under the high flow rate.The wear area of the impeller blade expands with the increase of the flow rate,and the wear degree is most serious at the head of the blade.The wear rate and wear area of the space guide vane increase with the increase of the flow rate,and the most serious is located at the pressure surface of the blade near the outer edge under the high flow rate.The maximum wear rate of the first-stage impeller and space guide vane is the largest,and the maximum wear rate of the impeller and space guide vane gradually decreases with the increase of the number of stages.The maximum wear rate of the impeller under the small flow condition is the largest and the maximum wear rate of the impeller under the rated flow condition is the smallest.In the first-stage,the maximum wear rate is 33.5 times and 8.5 times of 2 m^(3)/h and 4 m^(3)/h,respectively,when the flow rate is 6 m^(3)/h.The maximum wear rate of the first-stage space guide vane is greatly affected by the flow rate.