A study on periodic boundary condition in direct numerical simulation for gas–solid flow

作     者：Shiwen Liu Xiaowen Liu Feiguo Chen Limin Wang Wei Ge Shiwen Liu;Xiaowen Liu;Feiguo Chen;Limin Wang;Wei Ge

作者机构：State Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical EngineeringUniversity of Chinese Academy of SciencesBeijing 100049China 

出 版 物：《Chinese Journal of Chemical Engineering》 (中国化学工程学报（英文版）)

年 卷 期：2020年第28卷第1期

页      面：236-241页

核心收录：

学科分类：081704[工学-应用化学] 07[理学] 070304[理学-物理化学(含∶化学物理)] 08[工学] 0817[工学-化学工程与技术] 0703[理学-化学] 

基　　金：Supported by the National Natural Science Foundation of China(21821005,91834303) Science Challenge Project(TZ2016001) the Key Research Program of Frontier Science of the Chinese Academy of Sciences(QYZDJ-SSW-JSC029) the Strategic Priority Research Program of the CAS(XDA21030700) 

主　　题：Direct numerical simulation Periodic boundary condition Two-region periodic boundary condition Gas–solid flow Heterogeneity 

摘      要：Direct numerical simulation(DNS) of gas–solid flow at high resolution has been carried out by coupling the lattice Boltzmann method(LBM) for gas flow and the discrete element method(DEM) for solid particles. However,the body force periodic boundary condition(FPBC) commonly used to cut down the huge computational cost of such simulation has faced accuracy concerns. In this study, a novel two-region periodic boundary condition(TPBC) is presented to remedy this problem, with the flow driven in the region with body force and freely evolving in the other region. With simulation cases for simple circulating fluidized bed risers, the validity and advantages of TPBC are demonstrated with more reasonable heterogeneity of the particle distribution as compared to the corresponding case with FPBC.