Numerical simulation of local and global mixing/segregation characteristics in a gas–solid fluidized bed

作     者：Zhen Wan Youjun Lu Zhen Wan;Youjun Lu

作者机构：State Key Laboratory of Multiphase Flow in Power EngineeringXi’an Jiaotong UniversityXi’an 710049China 

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

年 卷 期：2022年第35卷第4期

页      面：72-86页

核心收录：

学科分类：080706[工学-化工过程机械] 08[工学] 0807[工学-动力工程及工程热物理] 

基　　金：supported by the National Key Research and Development Program of China(2020YFA0714400) the National Nature Science Foundation of China(51925602,51888103) 

主　　题：Discrete element method Solids mixing Binary mixtures Fluidized bed 

摘      要：Researches on solids mixing and segregation are of great significance for the operation and design of fluidized bed *** this paper,the local and global mixing and segregation characteristics of binary mixtures were investigated in a gas–solid fluidized bed by computational fluid dynamics-discrete element method(CFD-DEM)coupled approach.A methodology based on solids mixing entropy was developed to quantitatively calculate the mixing degree and time of the *** mixing curves of global mixing entropy were acquired,and the distribution maps of local mixing entropy and mixing time were also *** comparing different operating conditions,the effects of superficial gas velocity,particle density ratio and size ratio on mixing/segregation behavior were *** showed that for the partial mixing state,the fluidized bed can be divided into three parts along the bed height:complete segregation area,transition area and stable mixing *** areas showed different mixing/segregation *** gas velocity promoted the local and global mixing of binary *** increase in particle density ratio and size ratio enlarged the complete segregation area,reduced the mixing degree and increased the mixing time in the stable mixing area.