锅炉变负荷运行的炉膛热流量分布

Heat Flux Profile of the Furnace Wall of a Station Boiler at Different Loads

测量了一台300,MW煤粉炉炉壁不同高度的热流量,研究了热流量的分布规律,结果表明,不同负荷下,炉内热流量分布规律有显著差异,与高负荷相比,低负荷运行炉内热流量不均匀性更高;当燃烧器分两组布置,且组间距较大时,炉内热流量在高负荷时呈现"马鞍型"分布;热流量分布还受风、粉投入状态的影响;空气分级燃烧技术改变了燃料的燃烧分布,因而也改变炉内热流量分布,与传统燃烧技术相比,采用分级燃烧技术时,炉内辐射热流峰值(即火焰中心)的位置约提高了30%的炉膛高度.

Heat fluxes on furnace walls are measured and investigated in a commercial 300 MWe pulverized coal boiler in this paper, the results indicate that the fumace heat flux profile is significantly different at various loads, the lower the load, the greater the heat flux heterogeneity along the vertical height. When the burners are arranged in two groups, and the spacing of the group is larger, fumace heat flux profile show ＂saddle＂ distribution during high load operation, the profile is also affected by air and fuel distribution. Air staged combustion technology in modem large-capacity boilers has changed the distribution of fuel combustion, and consequently changed the heat flux profile. Furnace heat radiation peak position move upwardly 30% of the fumace height in air staged cnrnbustinn