沿空巷破碎煤体自燃耗氧及升温特征数值模拟
Numerical Simulation on Oxygen Consumption and Temperature Rising of Broken Coal Spontaneous Combustion in Gateway Retained Along Goaf
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摘要: 为研究巷道顶煤和煤柱破碎后由漏风引起的自燃耗氧及升温规律,在质量、动量和热量守恒模型的基础上利用FLUENT软件求解了沿空巷周围破碎煤体的稳态氧气分布和温度的动态变化过程。计算结果表明:在煤柱较完整的情况下,顶煤的氧气浓度分布高于煤柱,但二者都具有自然发火的危险。由于散热作用,高温区离二者的漏风边界都有一定的距离,顶煤升温速率较煤柱更快。在改变漏风强度后,高温区位置和范围也会随之改变。此研究结论可以帮助缩小现场火源区的寻找范围,以便及时采取措施抑制自燃。Abstract: In order to study the spontaneous combustion oxygen consumption and temperature rising law due to the air leakage when the top coal and coal pillar br oken in the gateway, based on the quantity, momentum and heat conservation model, the FLUENT software was applied to obtain the stable oxygen distribution and te mperature dynamic variation process of the broken coal mass around the gateway along the goaf. The calculation result showed that when the coal pillar was in complet ed condition, the oxygen content distribution in the top coal would be higher than the coal pillar and both the top coal and coal pillar would have the danger of the spont aneous combustion.Due to the heat radiation function, the air leakage boundary of the top coal and coal pillar to the high temperature zone both would have a certain di stance.The temperature rising rate of the top coal would be faster than the coal pillar.When the air leakage strength changed, the high temperature zone location and SC ope would be changed.The study conclusion could assist to reduce the seeking scope of the site fire zone and could be favorable to timely make the spontaneous comb ustion control measures.