角联管网瓦斯爆炸超压演化及火焰传播特性研究

Study on methane explosion overpressure evolution law and flame propagation characteristics in diagonal pipe networks

为了探索瓦斯在煤矿井下复杂巷网内爆炸后的超压演化规律及火焰传播特性,在实验室自行搭建了瓦斯爆炸试验系统,对甲烷体积分数为9.5%的瓦斯爆炸爆燃波传播规律进行了试验研究,并对瓦斯爆炸超压及火焰传播过程进行了数值模拟。试验与数值模拟结果表明:管网角联分支中,甲烷-空气预混气体爆炸后由于爆炸压力波的叠加,形成超压增高区域,但产生的火焰波很微弱,温度较低。并联分支中,随着爆燃波传播距离的增加,超压峰值和焰面传播速度呈逐渐减小的趋势,而火焰持续时间呈先增加、再减小的趋势。试验中火焰的最大传播距离为18.75 m,而数值模拟的传播距离为21.25 m,但试验值和模拟值的变化趋势一致。研究结论可对煤矿井下复杂巷道内瓦斯爆炸灾害的防控及救灾提供理论支持。

In order to explore the overpressure evolution law and flame propagation characteristics after methane explosion in a complex un⁃derground network of coal mines,a methane explosion test system was built in the laboratory,the propagation law of the deflagration wave of a gas explosion with a methane volume fraction of 9.5%has been experimentally studied,and the overpressure and flame propagation process of the gas explosion have been numerically simulated.The test and numerical simulation results show that in the diagonal branch of the pipe network,the methane-air premixed gas explodes due to the superposition of the explosion pressure wave,forming an area of increased over⁃pressure,but the flame wave generated is very weak and the temperature is low.In the parallel branch,with the increase of the propagation distance of the deflagration wave,the peak overpressure and the propagation velocity of the flame surface gradually decrease,while the flame duration first increases and then decreases.The maximum propagation distance of flame in the experiment is 18.75 m,while the propagation distance of the numerical simulation is 21.25 m,but the overall change law of experimental value and simulation value is the same.The re⁃search conclusions can provide theoretical support for the prevention,control and disasters in complex roadways in coal mines.