宽筛分流化床气固两相流动结构离散颗粒模型  

Discrete Particle Simulation of Flow Structure in Gas Fluidized Bed with Particle Size Distribution

作　　者：周浩生[1] 陆继东[1] 钱诗智[1] 

机构地区：[1]华中理工大学煤燃烧国家重点实验室

出　　处：《燃烧科学与技术》1999年第3期270-275,共6页Journal of Combustion Science and Technology

基　　金：博士后科学基金;国家自然科学基金

摘　　要：建立了适合描述宽筛分流化床气 固两相流动结构的离散颗粒模型。颗粒的运动满足牛顿第二定律 ,流体相的运动规律由局部平均的纳维 斯托克斯方程求解 ,两相间的耦合由牛顿第三定律决定。对宽筛分流化床中气泡的形成、颗粒的流化过程进行了数值模拟 ,结果与实验现象相符合 ;模拟结果还发现单颗粒的运动速度表现出不可预测特性 ,颗粒的总体速度不完全满足正态分布。A discrete particle model of a gas fluidized bed with particle size distribution has been developed.The motion of individual particles is obtained by solving Newtons second law of motion and gas flow by the Navier Stokes equation based on the concept of local average.The coupling of particles and gas is achieved directly by applying the principle of Newtons third law of motion to the discrete particle.Three simplified assumptions are made in the particle particle (or wall) collisional model,that is,the collisions are instantaneous,completely elastic and the rotation of the particles is insignificant.The simulation results of bubble formation at a single orifice and the fluidization process of uniform inlet air in two dimensional fluidized bed are in good agreement with the experiments of other authors.It also shows that the velocity of single particles and the velocity distribution function of particles are inpredictable and non Gaussian.

关 键 词：流化床 气固两相流动 离散颗粒模型 颗粒分布 

分 类 号：TB126[理学—工程力学] O359[理学—力学]