中文摘要：

为了在理论上分析注氮后采空区自燃环境和状态的变化情况,通过FLUENT软件求解包含多孔介质中动量、质量和热量传递关系的数学模型研究了注氮前后采空区自燃带范围的改变,以及降温范围和降温幅度.结果表明：自燃带分布在进回风侧呈不均匀对称分布,注氮后氧化带范围出现回缩前移,注氮口附近降温明显,降温幅度从注氮近点至远点依次降低,降温范围随着时间增加而扩大.研究结果表明注氮对采空区的降温存在一个时间上的延迟,现场施工应综合考虑多种客观因素对注氮起效时间进行预估.

英文摘要：

Aiming at theoretical analysis of the change of spontaneous combustion environments and status after nitrogen injection,the software FLUENT was used to solve the mathematical model including transfer relation of mass,energy and momentum in porous media.Besides,the spontaneous combustion area,cooling scope and cooling range were studied.The results show that the distribution of spontaneous combustion area is asymmetric between inlet side and outlet side and the combustion area scope becomes narrow after nitrogen injection.Moreover,the cooling range near injection hole is distinct and this cooling range decreases from near point to farther point,and the influence scope increases by the time.The research conclusion theoretically indicate the time delay for cooling goaf temperature exiting in the nitrogen injection process,hence the estimating of onset time should be made by integrated factors in the site.