煤矿巷道瓦斯爆炸后的热损伤分析研究

Thermal Damage Analysis Following Gas Explosions in Coal Mine Roadways

摘要: 煤矿巷道瓦斯爆炸后的产物输运与热暴露仍缺乏系统认识。采用FLACS建立200 m长、4 m × 4 m的一端封闭、一端敞开直巷模型，设置7.5%、9.5%、11.5%甲烷浓度和5、10、15 m填充长度，分析燃烧产物、超压及温度时程。结果表明，浓度效应呈非线性：10 m填充时，9.5%工况最大正超压约51 kPa，11.5%工况产物前缘达101 m；0.5~20 m峰值温度为2000~2300 K，填充长度增加使热扰动扩展至80~90 m。峰值超压、峰值温度与累计热暴露的排序并不一致，可为理想化直巷热环境分区提供依据。

Abstract: The transport of combustion products and the associated thermal exposure following gas explosions in coal mine roadways remain insufficiently understood. In this study, FLACS was used to establish a 200 m long straight-roadway model with a cross-section of 4 m × 4 m, with one end closed and the other open. Methane concentrations of 7.5%, 9.5%, and 11.5% and gas filling lengths of 5, 10, and 15 m were considered to investigate the evolution of combustion products, explosion overpressure, and temperature histories. The results reveal a nonlinear effect of methane concentration. At a filling length of 10 m, the maximum positive overpressure reached approximately 51 kPa under the 9.5% methane condition, whereas the combustion-product front propagated to 101 m under the 11.5% methane condition. Peak temperatures within 0.5~20 m ranged from approximately 2000 to 2300 K. Increasing the gas filling length extended the thermally disturbed region to approximately 80~90 m. Moreover, the rankings of peak overpressure, peak temperature, and cumulative thermal exposure differed among the investigated conditions. These findings provide a basis for thermal-environment zoning in idealized straight coal mine roadways.