摘要
针对传统曳力模型难以准确预测气固相间曳力的问题,考虑到计算精度和模型通用性,选用经过介尺度修正的EMMS-1M曳力模型耦合双流体模型,模拟了颗粒直径和进口气速对空气反应器冷态流化和热态化学反应的影响。结果表明:颗粒直径减小和进口气速增加,使床层气体压力分布更加均匀,床层轴向颗粒体积分数降低,床层颗粒返混现象减弱,颗粒轴向速度增加,温度升高促进反应正向进行,氧气转化率升高;进口气速增加,使颗粒在床层分布均匀,气固混合彻底,促进了化学反应,但进口气速过高,会携带出大量的颗粒,且在床层的停留时间减少,不利于气固化学反应的发生。
Aiming at the problem that the conventional drag force model is difficult to accurately predict the gas-solid interphase drag force,considering the calculation accuracy and model generality,the EMMS-1M drag force model with mesoscale correction coupled with the two-fluid model was chosen to simulate the effects of particle size and inlet gas velocity on the cold-state fluidization and thermal chemical reactions in the air reactor.Results show that:the decrease of particle size and increase of inlet gas velocity result in uniform bed gas pressure distribution;the bed axial particle concentration decreases,the bed particle mixing return phenomenon can be weakened,and the axial velocity of particles increases.Increasing temperature promotes the reaction to proceed positively and increases the oxygen conversion rate.The increase of inlet gas velocity leads to uniform particle distribution in the bed and complete gas-solid mixing,which promotes the chemical reaction.However,too high inlet gas velocity carries out many particles,and the residence time in the bed is reduced,which is not conducive to the occurrence of the gas-solid chemical reaction.
作者
李慧君
王业库
鲁许鳌
张久意
LI Huijun;WANG Yeku;LU Xuao;ZHANG Jiuyi(School of Energy,Power and Mechanical Engineering,North China Electric Power University,Baoding 071003,Hebei Province,China)
出处
《动力工程学报》
CAS
CSCD
北大核心
2023年第7期815-822,834,共9页
Journal of Chinese Society of Power Engineering
关键词
气固两相流
化学反应
介尺度
数值模拟
gas-solid two-phase flow
chemical reaction
medium scale
numerical simulation
