摘要
采用离散单元法分析了非均匀布风方式下流化床内的气固流动特性.数值模拟结果表明:床内存在大尺度的颗粒横向循环流动;高风速区为气泡活跃区域,气泡尾涡裹挟颗粒上升是形成内循环的关键环节;供风非均匀程度越大,颗粒内循环力度越强烈;改变风速,颗粒流量变化显著;倾斜布风板设计有利于促进颗粒定向循环过程.
Internally circulating fluidized beds play an important role in fields of energy and chemical industry. The hydrodynamics of the gas-solid flow in a fluidized bed with uneven gas supply was studied by using discrete element method （DEM）. The results indicate that there are large scale particle circulations in the lateral direction. The analysis shows that the zone with faster gas feed is a bubble active zone, where there is an upward particles stream resulted from the transport of the bubbles, which is thought to be an important factor causing the circulating particle stream in the fluidized column. Moreover, the more uneven the gas is supplied, the more intensive the particle circulation is. And the particle flux is sensitive to the change of the gas velocity. The design of an inclined distributor helps to enhance such directional circulation in the bed.
出处
《上海交通大学学报》
EI
CAS
CSCD
北大核心
2007年第3期347-351,共5页
Journal of Shanghai Jiaotong University
关键词
内循环流化床
非均匀布风
倾斜布风板
离散单元法
颗粒流量
internally circulating fluidized bed （ICFB）
uneven gas supply
inclined distributor
discrete element method （DEM）
particle flux
