离心泵转轮内流动特性及磨损数值预测

Numerical Simulation and Prediction of Flow Characteristics and Wear in the Impeller of a Centrifugal Pump

我国黄河沿线取水泵站水泵机组存在严重的泥沙磨损问题。研究对象为一双吸离心泵,采用固液两相流数值模拟预测了泵内粒子运动规律和磨损特性。结果表明:流量对转轮内粒子的运动特性和磨损特性有着显著的影响。在不同流量工况下,转轮内的磨损位置和磨损率明显不同,叶片壁面总磨损率与流量工况成正相关变化,随流量的增加而增加。在小流量工况下,转轮内存在的漩涡和二次流对颗粒的轨迹有较大的影响。漩涡的存在会改变粒子浓度分布,加剧局部的摩擦磨损。研究结果为泵内磨损预测和设计提供理论指导,具有重要的学术意义和工程价值。

There are serious sediment wear problems in the water pump units of water intake pump stations along the Yellow River in China.The research object of this paper is a double suction centrifugal pump. The particle motion law and wear characteristics in the pump are predicted by solid-liquid two-phase flow numerical simulation. The results show that the flow rate has a significant effect on the motion and wear characteristics of the particles in the runner. Under different flow conditions, the wear position and wear rate in the runner are obviously different. The total wear rate of blade wall changesis positively correlated withthe flow conditions and increases with the increase in the flow.Under the condition of small flows, the vortex and secondary flow in the runner have a great influence on the trajectory of particles. The existence of vortex will change the particle concentration distribution and aggravate the local friction and wear. The research results of this paper provide a theoretical guidance for the prediction and design of the pump internal wear, and have important academic significance and engineering value.