基于“O”型冒落及耗氧非均匀采空区自燃分布特征

Study on spontaneous combustion distribution of goaf based on the "O" type risked falling and non-uniform oxygen

从采空区自燃温度场计算角度,研究了基于"O"型冒落压实及耗氧非均匀性采空区自燃分布特征。建立了采空区非线性渗流-多组分气体-温度场和非均匀耗氧的数值模型,该模型考虑了矿井通风和工作面推进的动态变化;给出一种按"O"型圈压实分布来描述顶板岩层冒落的模型表达式;考虑到灌浆、灌注水、喷洒阻化剂和局部风流变化等导致采空区耗氧非均匀性,构造了阻化后耗氧非均匀0-1随机变化模型;模拟结果中表明(显示),尽管区域耗氧存在波动,阻化后的采空区整体耗氧能力在下降,表征温度有所降低,CO分布区域大大缩小,模拟结果符合现场实际情况。研究指出采空区耗氧非均匀性模型,能够解释实际采空区自燃升温的突变性和因素多变性的影响过程,成果对于工作面后方采空区遗留煤的防灭火工作起到了辅助指导作用。

From the point of calculating spontaneous combustion temperature field for goaf,distribution characteristics of spontaneous combustion for goaf based on the ＂O＂ type risked falling and non-uniform oxygen consumption was studied.A numerical model of nonlinear seepage-multicomponent gas-temperature field and the non-uniform oxygen consumption for goaf was established,which took into account the dynamic changes of mine ventilation and working face forward.One kind of model expression was given that describes the falling roof strata according to ＂O＂ type circle compaction distribution.Allow for grouting,injecting water,spraying inhibitor,and the changes of local air current leading to non-uniformity of oxygen consumption for goaf,the 0-1 random change model of non-uniform oxygen consumption after resistance was built.The results show that the ability of overall oxygen consumption is declining for goaf after resistance,the temperature increases,and the distribution area of CO has greatly reduced after resistance though regional oxygen consumption exists fluctuations,the results is close to the actual situation.The research points out that the non-uniformity model of oxygen consumption for goaf can account for the influence process of mutability and factors denaturations of the temperature rising process caused by spontaneous combustion for actual goaf.It plays an assist instruction role on fire prevention and extinguishing of survived coal in goaf behind working faces.