循环流化床锅炉一次风室送风口的改进设计  

Improved Design of Primary Chamber Inlet Port of Circulating Fluidized Bed Boiler

作　　者：邹爱红[1] 孙保民[1] 鲍震[2] 

机构地区：[1]华北电力大学电站设备状态监测与控制教育部重点实验室,北京102206 [2]中国电力科学研究院,北京100192

出　　处：《动力工程》2009年第7期632-634,663,共4页Power Engineering

摘　　要：针对循环流化床锅炉布风板处压力分布不均的现象进行了分析,提出在一次风口处加装散流器式导流装置的改进方案,并利用Fluent软件对改进前后一次风室的流场进行了数值模拟.结果表明:改进前,由于风口与边界之间、2个一次风口之间间距较大,在射流卷吸作用下,一次风入口与边界以及2个入口之间形成较大的回流区,气流向下运动,易抽吸炉渣,影响锅炉的经济性;改进后,一次风室内大回流区变小,在布风板下形成较宽的静压层,在风口附近压力较小,随着气流的扩散,动压逐渐转变成静压,静压力逐渐变大,布风板处压力分布均匀,避免了气流向下的抽吸现象,可有效改善布风板处压力分布不均的问题.The phenomenon of uneven pressure distribution around grid plate of circulating fluidized bed （CFB） boiler was analyzed. The improved scheme of adding directors of diffuser type at primary air ports was proposed. Software Fluent was used to numerically simulate the flow field in primary chamber before and after retrofit. Results show that before retrofit, due to the large space between air port and the border, as well as between two primary air ports, large return flow zones are formed between primary air port and the border, as well as between two primary air ports by the effect of jet entrainment. The stream flows downwards and takes in the furnace slag, which influences the economy of the boiler. After retrofit, the large return flow zones in primary chamber become small, a rather wide static pressure level is formed under the grid plate. The pressure near air port is small, and with the diffusion of the stream, the dynamic pressure gradually transforms into static pressure. As a result, the static pressure becomes big, andthe pressure distribution around grid plate becomes uniform, avoiding the draw off phenomenon occurs in downward stream. Thus the uneven pressure distribution around grid plate can be improved.

关 键 词：循环流化床锅炉 一次风室 送风口 静压 数值模拟 

分 类 号：TK229.66[动力工程及工程热物理—动力机械及工程]