In respect of the influence of tail roadway methane drainage pattern on spontaneous combustion in long wall gob area, the coal spontaneous combustion heating up model containing heating resource and heat transfer relationship between air and coal was established. The steady oxygen contribution and unsteady temperature change history under different condition were calculated using FLUENT software. Compared with no-methane drainage situation, depth methane drainage with high flux will change flow pattern in gob area dramatically and leads the oxygen into depth of gob. Thus the rate of temperature rise can accelerate obviously and high temperature region moves back towards depth of gob. Nitrogen injection can decrease the oxygen concentration to low level within certain scope where high temperature region has different degree control effect by nitrogen injection with times but has little help for high temperature scope near drainage hole.%针对尾巷抽采瓦斯抽放对长壁工作面采空区煤自燃升温影响的问题,利用化学反应动力学理论和换热关联式建立了包含热源和空气与固体换热关系的煤自燃升温模型,借助FLUENT软件计算了不同条件下采空区氧气稳态分布情况和温度动态变化过程.结果表明:同未抽放相比,深部大流量的瓦斯抽采会显著改变采空区流态,造成氧气向采空区纵深发展,煤自燃引起的升温速率会明显加快,高温区域范围扩大并向后移动.注氮可以将一定范围内的氧气浓度控制在较低的水平,并对控制范围内高温区域的升温速率随着时间推移起到不同程度的抑制作用,但对抽放口附近区域的温度抑制帮助不大.
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