巷道冒落区瓦斯积聚的数值模拟及应用

Numerical simulation of methane accumulation in roof falling zone of roadway in coal mine and its application

巷道冒落区的瓦斯积聚,既可能会引起瓦斯燃烧或爆炸,又会导致煤自燃,同时瓦斯随风流进入巷道也会引起事故,构成煤矿安全生产的重大隐患。文中采用计算流体动力学软件FLU-ENT对巷道冒落区的瓦斯积聚和扩散情况进行了数值模拟,重点比较了不同风速条件下瓦斯积聚的差异。巷道风速越大,瓦斯积聚越弱,但是风速高于临界风速时,并不能显著地降低积聚瓦斯的最高浓度;同时模拟结果表明冒落区内设置导风板对稀释积聚瓦斯具有良好的效果。模拟结果进一步验证了实际预防冒落区瓦斯积聚措施的合理性和科学性。

Methane accumulation in roof falling zone will lead not only to gas combustion but also to coal spontaneous combustion. Moreover, methane can also flow into roadway with wind current forming sefusion in roadway. The research mainly discusses the influence of wind velocity on methane accumulation. It shows that the accumulated-methane concentration decreases with the increase of wind velocity. However, wind current with above critical speed can not weaken gas accumulation dramatically. Furthermore, the simulation results also make it clear that the air dam set up in roof falling zone will dilute accumulated-methane significantly. The simulation works verify the operational methane accumulation prevention measures to be reasonable and scientific.