粗糙颗粒动理学及流化床内气固流动的数值模拟  

Kinetic theory of rough spherical particles and numerical simulation of gas-solids flow in fluidized bed

作　　者：陈巨辉[1] 杜小丽[1] 孙立岩[1] 徐鹏飞[1] 郝振华[1] 陆慧林[1] 

机构地区：[1]哈尔滨工业大学能源科学与工程学院,黑龙江哈尔滨150001

出　　处：《化工学报》2011年第5期1197-1204,共8页CIESC Journal

基　　金：国家自然科学基金项目(51076040)~~

摘　　要：基于气体分子动理学和颗粒动理学理论,考虑颗粒旋转流动对颗粒碰撞能量交换和耗散的影响,建立粗糙颗粒动理学。采用Chapman-Enskog颗粒速度分布函数,提出了颗粒相应力、热通量和颗粒碰撞能量耗散计算模型。采用欧拉-欧拉气固双相流模型,数值模拟鼓泡流化床内气体-颗粒两相流动特性。模拟结果得到了床内颗粒相速度和脉动速度分布,与Yuu等实验结果相吻合。分析不同的切向弹性恢复系数对颗粒相拟总温的变化规律,结果表明在低颗粒浓度时颗粒拟总温随切向弹性恢复系数而增加。Particle rotation,which has been less considered in particle kinetic model,plays an important role in gas-solids flow.Kinetic theory of rough spherical particles was proposed on the basis of kinetic theory of gases and kinetic theory of granular flow with the consideration of energy transport and dissipation by collision of particles.The models for solids phase stress,thermal flux and collisional energy dissipations of particles were presented by using Chapman-Enskog velocity distributions.Flow behavior of gas and particles was simulated by gas-solids two-phase flow model in a bubbling fluidized bed.Predicted velocity distribution and fluctuating velocity of particles were in agreement with experimental data measured by Yuu et al（2000）in a bubbling fluidized bed.The distribution of granular temperature,changing with concentration tended to be similar with the prediction by kinetic theory of granular flow.The effect of tangential restitution coefficient on fluctuating energy of particles was analyzed.Simulated results showed that at a low concentration of particles the fluctuating kinetic energy of particles increased with increasing tangential restitution coefficient.

关 键 词：颗粒旋转 粗糙颗粒动理学 气固两相流 流化床 

分 类 号：TK229[动力工程及工程热物理—动力机械及工程]