基于全耦合CFD-DEM方法的多级混流泵磨损模拟研究

Erosion of multistage mixed flow pump based on fully coupled CFD-DEM method

磨损是导致多级混流泵失效的主要原因,采用CFD(Computational Fluid Dynamics)数值模拟方法是设计优化该类泵抗磨损性能的重要手段。该文基于CFD-DEM(Computational Fluid Dynamics-Discrete Element Method)方法,通过自定义相间作用建立了流体与颗粒的全耦合模型,通过与已有实验结果对比,验证了该计算模型的准确性,研究了颗粒浓度、形状和小流量工况对泵叶片磨损的影响。结果表明,混流泵叶轮叶片磨损主要发生在头部和尾部靠后盖板一侧,颗粒浓度和形状对泵叶片磨损位置影响较小,磨损量随浓度增大和球形度减小而急剧增加,另外,流道内颗粒滞留数量与球形度大小有关。

Erosion is the main matter for the damage of multi-stage mixed-flow pumps.CFD(Computational Fluid Dynamics)simulation method is an important method to design and optimize pumps to have a long running time.A user-defined function used to establish a fully coupled model of fluid and particles considering interphase interactions in this paper.The accuracy of model is verified by comparing with existing experimental results.And erosion of pump blades under different particle concentration,shape and small flow conditions are studied.The results show that the erosion of the impeller blades of the mixed-flow pump mainly occurs on the head and tail side of the hub.The particle concentration and shape have a small effect on the wear position of the pump blade.In addition,the number of particles retained in the flow channel is related to the sphericity.