流化床半焦燃烧的DEM三维数值模拟  

3D CFD-DEM Simulation of Char Combustion in a Fluidized Bed

作　　者：谢俊[1] 钟文琪[1] 邵应娟[1] 李开喜[2] XIE Jun;ZHONG Wen-Qi;SHAO Ying-Juan;LI Kai-Xi(Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, China;Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, China)

机构地区：[1]能源热转换及其过程测控教育部重点实验室(东南大学),能源与环境学院,南京210096 [2]中国科学院山西煤炭化学研究所,太原030001

出　　处：《工程热物理学报》2019年第6期1307-1312,共6页Journal of Engineering Thermophysics

基　　金：NSFC-山西煤基低碳联合基金重点项目(No.U1510204);国家重点研发计划(No.2016YFB0600802);国家自然科学基金(No.51606039)

摘　　要：气相场基于欧拉法,颗粒相采用离散单元法(DEM),同时考虑气固流动、传热传质以及化学反应,构建了基于CFD-DEM法的稠密气固系统热转化过程的并行数值模拟方法及平台,并对实验室规模的流化床半焦燃烧过程进行了研究。通过准三维流化床中单颗粒燃烧模拟对所建立的模型进行了验证,其后考察了不同过量空气系数下的三维流化床半焦燃烧,获得了颗粒流型、空隙率、温度、组分浓度等分布,结果表明高气量增加了反应初始阶段半焦燃烧速率,加速了半焦温度的升高。The gas phase is modelled by Eulerian method and the solid phase by discrete element method(DEM). The gas-solid flow, heat and mass transfer, and chemical reaction are simultaneously considered. A parallel numerical method and platform for heat conversion process of dense gas-solid system is established, which is applied to the simulation of char combustion in a lab-scale fluidized bed. Based on the validation by the single particle combustion in a quasi-three dimensional(3 D)fluidized bed, the combustion processes in a 3 D fluidized bed under different air ratios are studied.The gas-solid flow pattern, profiles of voidage, temperature, and gas composition are obtained. The results show that char combustion rate of initial reaction stage increases with the increasing air ratio,accelerating the rise of char temperature.

关 键 词：DEM 燃烧 气固流动 三维数值模拟 

分 类 号：TK17[动力工程及工程热物理—热能工程]