Numerical investigation of particle saltation in the bed-load regime

作     者：JI ChunNing ANTE Munjiza ELDAD Avital XU Dong JOHN Williams 

作者机构：State Key Laboratory of Hydraulic Engineering Simulation and SafetyTianjin University School of Engineering & Materials ScienceQueen MaryUniversity of London 

出 版 物：《Science China(Technological Sciences)》 (中国科学（技术科学英文版）)

年 卷 期：2014年第57卷第8期

页      面：1500-1511页

核心收录：

学科分类：0810[工学-信息与通信工程] 08[工学] 081502[工学-水力学及河流动力学] 0815[工学-水利工程] 0805[工学-材料科学与工程（可授工学、理学学位）] 0702[理学-物理学] 0812[工学-计算机科学与技术（可授工学、理学学位）] 

基　　金：supported by a Marie Curie International Incoming Fellowship within the seventh European Community Framework Programme(Grant No.PIIF-GA-2009-236457) the financial support of the Science Fund for Creative Research Groups of the National Natural Science Foundation of China(Grant No.51321065) Programme of Introducing Talents of Discipline to Universities(Grant No.B14012) National Natural Science Foundation of China(Grant Nos.50809047 and 51009105) Natural Science Foundation of Tianjin(Grant No.12JCQNJC02600) 

主　　题：particle saltation bed-load regime hydrodynamic forces turbulent channel flow 

摘      要：This paper numerically investigates particle saltation in a turbulent channel flow having a rough bed consisting of 2–3 layers of densely packed *** this study,we combined three the state-of-the-art technologies,i.e.,the direct numerical simulation of turbulent flow,the combined finite-discrete element modelling of the deformation,movement and collision of the particles,and the immersed boundary method for the fluid-solid *** we verify our code by comparing the flow and particle statistical features with the published data and then present the hydrodynamic forces acting on a particle together with the particle coordinates and velocities,during a typical *** found strong correlation between the abruptly decreasing particle stream-wise velocity and the increasing vertical velocity at collision,which indicates that the continuous saltation of large grain-size particles is controlled by collision parameters such as particle incident angle,local rough bed packing arrangement,and particle density,*** physical process is different from that of particle entrainment in which turbulence coherence structures play an important *** distribution functions of several important saltation parameters and the relationships between them are *** results show that the saltating particles hitting the windward side of the bed particles are more likely to bounce off the rough bed than those hitting the *** on the above findings,saltation mechanisms of large grain-size particles in turbulent channel flow are presented.