摘要
以一台660 MW机组的FW型W火焰锅炉为研究对象,提出了拱上布置燃尽风(OFA)技术及配套高效燃烧措施。建立了1:15气固两相冷态试验台,采用三维激光相位多普勒分析仪研究了OFA入射角度对炉内气固两相的平均速度、脉动速度、颗粒体积流量以及颗粒平均粒径等气固两相流动特性参数的影响。随着OFA入射角度的增加,浓煤粉气流的射流深度有所减小,固相颗粒在下炉膛的停留时间缩短。OFA气流穿透深度随入射角度增加呈先升高后降低的趋势。当入射角度为20°时,OFA气流在水平和竖直方向上的气固两相速度和脉动速度均衰减较慢,而且OFA气流与拱下回流区互不影响,能够与上行气流充分且剧烈的混合。对于拱上布置OFA,认为入射角度为20°较合适。
ABSTRACT:The arch-supplied OFA technology and matched efficient combustion measures were proposed for a FW type down-fired boiler. A gas/particle two phase cold airflow experimental system were established by modeling the utility boiler mentioned above with a proportion of 1:15. Three-dimensional particle dynamic analyzer (PDA) was used to measure the parameters such as the velocity of gas-solid phase, fluctuating velocity, particle volume rate and particle mean diameter in the model furnace. Gas/solid flow characteristics with different OFA injecting angle were investigated. With the increase of the OFA injecting angle, the injection depth of the fuel-rich airflow decrease, and the residence time of solid particle in the lower furnace shorten. The OFA penetration depth first increase and then decrease with the OFA injecting angle increasing. When the injecting angle is 20°, the gas-solid phase velocity and fluctuating velocity on the horizontal and vertical direction for the OFA airflow delay slowly, moreover, the OFA airflow and the recirculation zone below the arches did not affect each other. Therefore, the injecting angle 20° is more appropriate for the arch-supplied OFA program.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2015年第12期3081-3088,共8页
Proceedings of the CSEE