This paper presents numerical studies on the effects of atmospheric pressure fluctuations on hill-side coal fires and their surface anomalies. Based on the single-particle reaction–diffusion model, a formula to estim...This paper presents numerical studies on the effects of atmospheric pressure fluctuations on hill-side coal fires and their surface anomalies. Based on the single-particle reaction–diffusion model, a formula to estimate oxygen consumption rate at high temperature controlled by oxygen transport is proposed.Daily fluctuant atmospheric pressure was imposed on boundaries, including the abandoned gallery and cracks. Simulated results show that the effects of atmospheric pressure fluctuations on coal fires and surface anomalies depend on two factors: the fluctuant amplitude and the pressure difference between inlet(s) and outlet(s) of the air ventilation system. If the pressure difference is close to the fluctuant amplitude, atmospheric pressure fluctuations greatly enhance gas flow motion and temperatures of the combustion zone and outtake(s). If the pressure difference is much larger than the fluctuant amplitude, atmospheric pressure fluctuations exert no impact on underground coal fires and surface anomalies.展开更多
There are many potential hazards in the underground mining these include fire, explosion, inundation, roof collapse, toxic gases, chemical pollution, etc. Over past centuries, in US alone, more than 100 000 miners los...There are many potential hazards in the underground mining these include fire, explosion, inundation, roof collapse, toxic gases, chemical pollution, etc. Over past centuries, in US alone, more than 100 000 miners lost their life in different accidents. The primary safety methods used in underground mines concentrate on the monitoring of the hazardous gases, fire detection and ventilation. Using advanced instruments and monitoring techniques have significantly reduced the accidents in the modem mines. However despite the advancement of these monitoring facilities, accidents still occur in underground mining annually in the world, and many miners were killed because they were trapped and unable to escape due to blocked of exit access. Described a new development for the emergency evacuation system in underground mines and analyzed the advantages and disadvantages of the system. It is expected that the new system will greatly improve the emergency exit methods and save more lives in the future.展开更多
文摘This paper presents numerical studies on the effects of atmospheric pressure fluctuations on hill-side coal fires and their surface anomalies. Based on the single-particle reaction–diffusion model, a formula to estimate oxygen consumption rate at high temperature controlled by oxygen transport is proposed.Daily fluctuant atmospheric pressure was imposed on boundaries, including the abandoned gallery and cracks. Simulated results show that the effects of atmospheric pressure fluctuations on coal fires and surface anomalies depend on two factors: the fluctuant amplitude and the pressure difference between inlet(s) and outlet(s) of the air ventilation system. If the pressure difference is close to the fluctuant amplitude, atmospheric pressure fluctuations greatly enhance gas flow motion and temperatures of the combustion zone and outtake(s). If the pressure difference is much larger than the fluctuant amplitude, atmospheric pressure fluctuations exert no impact on underground coal fires and surface anomalies.
文摘There are many potential hazards in the underground mining these include fire, explosion, inundation, roof collapse, toxic gases, chemical pollution, etc. Over past centuries, in US alone, more than 100 000 miners lost their life in different accidents. The primary safety methods used in underground mines concentrate on the monitoring of the hazardous gases, fire detection and ventilation. Using advanced instruments and monitoring techniques have significantly reduced the accidents in the modem mines. However despite the advancement of these monitoring facilities, accidents still occur in underground mining annually in the world, and many miners were killed because they were trapped and unable to escape due to blocked of exit access. Described a new development for the emergency evacuation system in underground mines and analyzed the advantages and disadvantages of the system. It is expected that the new system will greatly improve the emergency exit methods and save more lives in the future.
