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在模拟工业煤粉炉燃烧环境的光学诊断型携带流煤粉反应器系统上开展了高温流动条件下煤粉着火特性研究,通过光学诊断技术获取煤粉火焰总光强分布和煤粉火焰中自由基OH*自发辐射强度分布,对不同反应环境下煤粉射流火焰着火延时和火焰中气相OH*着火延时对比研究,考察了环境氧浓度、环境温度、煤种对煤粉着火的影响.研究表明:着火延迟对于环境氧浓度更为敏感,随着环境氧浓度提高,粒径为53～80μm烟煤和褐煤着火延时及气相OH*着火延时几乎都线性下降,但气相OH*着火延时下降更慢;煤粉火焰主燃烧段长度和气相OH*主燃烧段长度都变短,前者始终比后者长;在10％～30％的氧浓度范围内,褐煤相对于高挥发分烟煤着火延时滞后,但主燃烧段长度更短.“,”An optical entrained flow pulverized coal reactor system simulating the combustion conditions of industrial pulverized coal boiler was employed to study ignition and combustion characteristics of pulverized coal under high temperature. The most important operation parameters, including ambient temperature, ambient oxygen concentration, coal ranks, on pulverized coal (PF) steam ignition were investigated. Ignition delay times of PF stream were achieved from distribution of the overall pulverized coal stream flame light intensity and OH* spontaneous light intensity with optical diagnostic technique. The results show that, the overall flame's and OH* ignition delay time of the bituminous and lignite pulverized coal (53～80μm) stream and the length of the main combustion zone decreases with the increase of ambient oxygen concentration, but OH* ignition delayfalls more slowly; the length of the main combustion zone of the pulverized coal stream flame is longer than the reaction zone expressed by OH* for the longer burning time of char, and they all become shorter with the increase of ambient oxygen concentration. For lignite, in the range of 10％～30％ oxygen concentration ignition delay time is relatively longer than bituminous,but the main combustion zone is shorter.