流化床内气固两相流模拟参数敏感性分析  

Sensitivity Analysis of Gas-Solid Two-Phase Flow Simulation in Fluidized Bed

作　　者：郑建祥[1] 丛云龙 Zheng Jianxiang;Cong Yunlong(School of Energy Resource and Power Engineering,Northeast Electric Power University,Jilin Jilin 132012)

机构地区：[1]东北电力大学能源与动力工程学院

出　　处：《东北电力大学学报》2019年第4期41-48,共8页Journal of Northeast Electric Power University

基　　金：吉林省科技厅十三五重点科技研发项目(20180201001SF);吉林市科技创新发展项目(201750238);吉林省教育厅十三五科研项目(JJKH20190703KJ)

摘　　要：利用CFD-DEM耦合模型,数值模拟了竖直微型流化床内粘性颗粒的流动过程,研究分析了对数值模拟准确性具有重要影响的气相壁面条件、网格尺寸大小和杨氏模量等敏感性参数.研究结果表明,气相壁面条件对固相流场的影响可以忽略.推荐使用2.5倍~4倍粒径大小的欧拉网格,以使计算网格内可以容纳足够数量的颗粒,进而满足数值模拟统计平均的要求.临界流化速度随颗粒杨氏模量的增加而明显减小;当采用较大的杨氏模量时,流化床内出现明显的环核结构,此时更为贴近对比文献中的实验现象.In this paper,the numerical simulation of viscous particle flow in a vertical micro-fluidized bed is carried out by using the cfd-dem coupled numerical simulation algorithm,which has an important influence on the accuracy of the numerical simulation of the gas wall conditions.The sensitivity parameters such as mesh size and Young’s modulus are studied and analyzed.The results show that the effect of gas wall conditions on solid flow field can be ignored.The recommended Euler mesh size should be 2.5~4 times the size of particle size,so as to ensure that it can accommodate enough particles to meet the requirements of numerical simulation statistical average.The critical fluidization velocity decreases obviously with the increase of Young’s modulus of particles,and the larger Young’s modulus is,the more obvious the ring nuclear structure of fluidized bed is,which is closer to the experimental phenomenon in the comparative literature.

关 键 词：细颗粒 CFD-DEM 粘性 数值模拟 杨氏模量 

分 类 号：TQ021.1[化学工程]