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在U+L型通风条件下,联络巷的存在对采空区遗煤自燃有重要的影响.为保证矿井安全生产,并为预防遗煤自燃提供依据,根据煤体低温氧化的反应机理,使用UDF将煤氧反应的机理编入FLUENT,对联络巷存在时采空区氧化升温带的分布规律进行多场耦合数值模拟研究.结果表明:联络巷的存在使采空区内风流场、氧浓度场及温度场都发生变化,氧化升温带不仅向回风侧偏移,而且向采空区深部移动且变宽;联络巷与工作面的距离影响氧化升温带的宽度,联络巷距工作面20 m时氧化升温带宽度最大约为25 m;反应进行10 d后,U+L型通风下采空区高温点的升温速率可达1.24 K·d-1,是U型通风的1.5倍,但联络巷相对工作面的位置对高温点几乎没有影响;与U型通风时相比,U+L通风时回风侧的温度场中联络巷口温度最高,而且比U型通风时相同坐标位置的温度平均每天高出4 K,随着联络巷与工作面距离的不断增加,联络巷口升温速率由0.1 K·d-1可升至0.9 K·d-1,这在整体温度场中虽然不属于高温区域,但具有很好的升温潜质.
Under the condition of U + L ventilation, the existence of communication lane has an important influence on spontaneous combustion of coal left by the goaf.In order to ensure safe production of coal mines and provide a basis for prevention of spontaneous combustion of coal, according to the reaction mechanism of low temperature oxidation of coal, UDF compiles the mechanism of coal-oxygen reaction into FLUENT, and conducts multi-coupling numerical simulation study on the distribution of oxidation and temperature rise in the gob as the contact lane exists.The results show that the existence of the contact lane makes the wind flow field, oxygen concentration Field and temperature field are changed, the oxidation temperature zone not only to the return air side offset, but also to the goaf deep mobile and widened; contact lane and the work surface distance affect the width of the oxidation zone, the contact lane from the face 20 m, the maximum width of the oxidation zone is about 25 m. After 10 days of the reaction, the heating rate at the high temperature point of the goaf under U + L ventilation is up to 1.24 K · d-1, which is 1.5 times that of the U-type ventilation Compared with U type ventilation, U + L ventilation has the highest contact temperature in the return air side of the return air, and the temperature is higher than that of the U type ventilation The average daily temperature is 4 K, with the laneway and working surface distance With the increase of temperature, the rate of temperature rise in contact lane can be increased from 0.1 K · d-1 to 0.9 K · d-1, which has good potential for warming even though it does not belong to the high temperature region in the whole temperature field.