布风装置对流化床流动特性的影响  

Influences of gas distributors on flow characteristics in fluidized beds

作　　者：张丹[1] 郭雪岩[1] 

机构地区：[1]上海理工大学能源与动力工程学院,上海200093

出　　处：《上海理工大学学报》2010年第3期268-272,共5页Journal of University of Shanghai For Science and Technology

基　　金：上海市浦江人才计划资助项目(07pj14072);上海市重点学科建设资助项目(J50501)

摘　　要：以欧拉双流体模型和颗粒动力学方法为基础,采用基于压力的PC-SIMPLE算法,标准k-ε的分散湍流模型,数值模拟了在3种不同气体布风装置下流化床内气固两相流动,获得了其床内颗粒体积分率和速度的分布规律.相对于单层多孔板流化床,管式和凹形多孔板流化床达到稳定流化状态的时间较短.在相同的床高和径向位置处,管式和凹形多孔板流化床内颗粒体积分率随时间的变化较强烈.不同布风装置的流化床总体上在床内形成了中心区域体积分率较小,向上运动;近壁面区域体积分率较大,向下运动的"环核"结构.Based on the Eulerian-Eulerian two-fluids flow model and the granule kinetics,numerical simulation was conducted to investigate the characteristics of gas-solid two-phase flow in fluidized beds with three different gas distributors, using the standard κ-ε dispersed turbulence model and the PC-SIMPLE algorithm. The instantaneous solid volume fraction and granule velocity were obtained. Fluidized beds with gas distributors of tube-type or concave perforated plate-type have shorter fluidization initialization time than the one with monolayer perforated plate gas distributor. At the same bed height and radical position, the solid volume fraction of the fluidized beds with tube-type or concave perforated plate-type distributors oscillates with higher frequency. In general, the three types of fluidized beds are characterized by a flow pattern that particles mainly flow upward with a low concentration in the central region of the beds but flow downward with relatively high concentration near the wall.

关 键 词：流化床 欧拉双流体模型 数值模拟 

分 类 号：TQ051.13[化学工程]