方形明槽湍流中颗粒卷起行为的数值模拟  

Numerical Simulation of Particle Resuspension in Turbulent,Open Square Duct Flows

作　　者：赵彦琳 王艳芝 姚军 ZHAO Yan-Lin;WANG Yan-Zhi;YAO Jun(Beijing Key Laboratory of Process Fluid Filtration and Separation,College of Mechanical and Transportation Engineering,China University of Petroleum-Beijing,Beijing 102249,China)

机构地区：[1]中国石油大学(北京)机械与储运工程学院过程流体过滤与分离技术北京市重点实验室,北京102249

出　　处：《工程热物理学报》2020年第5期1139-1145,共7页Journal of Engineering Thermophysics

基　　金：国家自然科学基金(No.51776225);中国石油大学(北京)科研基金(No.C201602)。

摘　　要：采用大涡模拟单向耦合拉格朗日颗粒跟踪技术的方法研究了高雷诺数下(Re=2.5×10^5)方形明渠槽道湍流中颗粒的卷起行为。模拟结果表明,湍流驱动产生的二次流对颗粒的悬浮起着重要的作用,且颗粒的卷起率随着颗粒直径的增大而减小。剪切升力被发现可以促进颗粒的卷起,且这种作用随着粒径的增大而增强。与封闭槽道流相比,明渠槽流截面的二次流强度较弱,从而造成其卷起率分布波动较小。动力学分析表明,对于小颗粒,其卷起行为主要取决于曳力,而对大颗粒,升力起主导作用。Large eddy simulation is used to study particle resuspension in turbulent square,open duct flows at Re=2.5×10^5,combined with a Lagrangian particle tracking technique of one-way coupling.Simulation results show that the turbulence-driven secondary flow plays a key role in particle resuspension,with the resuspension rate decreasing with particle size.The shear-lift force is found to be able to promote particle resuspension,and this function enhances with increasing of particle diameter.In comparison with closed duct flow,the strength of secondary flow in the open duct cross-section is weaker,which causes the smaller fluctuations of resuspension rate.The dynamic analysis indicates that it is the drag force dominating the resuspension of small particles,with large particles’motion mainly determined by lift force.

关 键 词：大涡模拟 湍流 二次流 颗粒卷起 明槽 

分 类 号：O359[理学—流体力学]