300MW循环流化床锅炉稀相区的传热研究  

Study of the Heat Transfer in the Sparse Phase Zones of a 300MW Circulating Fluidized Bed Boiler

作　　者：索疆舜 崔志刚[1] 侯致福 

机构地区：[1]太原理工大学电气与动力工程学院,山西太原030024 [2]山西平朔煤矸石发电有限责任公司,山西朔州036800

出　　处：《热能动力工程》2016年第9期69-74,135,共6页Journal of Engineering for Thermal Energy and Power

基　　金：山西省青年科技研究基金资助项目(2015021124)

摘　　要：本文针对燃烧煤矸石的循环流化床锅炉的传热情况展开研究,以山西平朔电厂1台300 MW的循环流化床锅炉为实例,采用环核模型和颗粒团更新模型,对稀相区的传热系数分布进行建模计算,本文所建模型考虑炉内床温实际分布特征,根据现场温度实测数据对模型进行修正,研究了对流和辐射换热系数在不同负荷下沿炉膛高度的变化情况。锅炉在较高负荷下运行时,负荷的波动对颗粒团壁面覆盖时均份额影响较小,继而对炉内对流换热影响较小。炉内环形区温度沿床高的偏差随负荷升高略有减小,且对辐射换热影响比对流换热大。随着负荷升高,对流换热系数沿炉高下降增大,而辐射换热系数沿炉高下降减小,高负荷时炉内总换热系数沿炉高下降25%左右,低负荷时沿炉高下降28%左右,高负荷下炉内沿高度温差更小,传热更稳定。The heat transfer in a CFD boiler burning gangue was studied. With a 300 MW CFD boiler in Shanxi Pingshuo Power Plant serving as an example,the core-annulus model and particle cluster update model were used to model establish and calculate the distribution of the heat transfer coefficient in the sparse phase zones as the focus. The model thus established has taken account of the actual characteristics of the distribution of the temperature in the circulating fluidized bed in the furnace and was corrected and updated according to the data of the temperature actually measured on the spot. Finally,changes of the convection and radiation heat exchange coefficient at various loads along the height of the furnace were studied. It has been found that when the boiler is operating at a relatively high load,the fluctuation in load has relatively small influence on the time-averaged particle cluster wall surface covering share and therefore,so does the fluctuation in load on the convection heat exchange inside the furnace. The deviation of the temperature in the annulus zones in the furnace along the height of the circulating fluidized bed will somehow decrease and has bigger influence on the radiation heat exchange than on the convection heat exchange. With an increase of the load,the decline of the convection heat exchange coefficient along the height of the furnace will increase while the decline of the radiation heat exchange coefficient along the height of the furnace will decrease. At a high load,the total in-furnace heat exchange coefficient along the height of the furnace will decrease by around 25%while at a low load will decrease by about 28%. At a high load,the temperature difference in the furnace along the height of the furnace will become smaller and the heat transfer will be more stable.

关 键 词：裤衩腿型循环流化床锅炉 煤矸石 稀相区 传热系数 

分 类 号：TK229.66[动力工程及工程热物理—动力机械及工程]