Numerical analysis of residence time distribution of solids in a bubbling fluidized bed based on the modified structure-based drag model

作     者：Zheng Zou Yunlong Zhao Hu Zhao Hongzhong Li Qingshan Zhu Zhaohui Xie Yingbo Li 

作者机构：State Key Laboratory of Multi-phase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Belting 100049 China Key Laboratory of Green Process and Engineering Institute of Process Engineering Chinese Academy of Sciences Belting 100190 China 

出 版 物：《Particuology》 (颗粒学报（英文版）)

年 卷 期：2017年第15卷第3期

页      面：30-38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] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

基　　金：国家自然科学基金 the State Key Development Program for Basic Research of China (973 Program) the Science Technology Service Network Initiative of the Chinese Academy of Sciences the Fund of the State Key Laboratory of Multiphase Complex Systems 

主　　题：FluidizationResidence time distribution Bubbling fiuidized bed Modified structure based drag mode Computational fluid dynamics CFD 

摘      要：The residence time distribution （RTD） of solids and the fluidized structure of a bubbling fluidized bed were investigated numerically using computational fluid dynamics simulations coupled with the modified structure-based drag model. A general comparison of the simulated results with theoretical values shows reasonable agreement. As the mean residence time is increased, the RTD initial peak intensity decreases and the RTD curve tail extends farther. Numerous small peaks on the RTD curve are induced by the back- mixing and aggregation of particles, which attests to the non-uniform flow structure of the bubbling fluidized bed. The low value of t50 results in poor contact between phases, and the complete exit age of the overflow particles is much longer for back-mixed solids and those caught in dead regions. The formation of a gulf-stream flow and back-mixing for solids induces an even wider spread of RTD.