Historically, there have been many occurrences of mine fires and explosions recorded in the United States and other countries that have demonstrated the existence of explosive methane–air mixtures, herein referred to as explosive gas zones (EGZs). The risk of mine explosions can increase if the EGZs migrate out from the gob into the surrounding mine entries. Fluctuating barometric pressure is the common cause for EGZs outflowing or outgassing from the gob. Numerical analysis using a 3D computational fluid dynamics method was developed to fully understand the outgassing phenomenon. A number of simulations using various magnitudes and periods of barometric pressure changes indicated that the EGZ outgassing potentially occurs due to lags in pressure, which are strongly influenced by mine conditions and ventilation systems. An early warning system with a real-time pressure monitoring and the application of gob ventilation boreholes are recommended to detect and mitigate explosion hazards from gob outgassing.

中文翻译：

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长壁煤矿瓦斯脱气与减缓研究

从历史上看，美国和其他国家记录了许多矿井火灾和爆炸事件，这些事件证明存在爆炸性甲烷-空气混合物，这里称为爆炸性气体区 (EGZ)。如果 EGZ 从采空区迁移到周围的矿井入口，则地雷爆炸的风险会增加。气压波动是 EGZ 从采空区流出或释气的常见原因。开发了使用 3D 计算流体动力学方法的数值分析，以充分了解除气现象。使用不同幅度和周期的大气压力变化进行的大量模拟表明，EGZ 脱气可能由于压力滞后而发生，而压力滞后受矿山条件和通风系统的强烈影响。