管内瓦斯爆炸传播影响因素及火焰加速机理分析

Analysis on flame acceleration mechanism and affecting factors of methane explosion propagation in duct

基于瓦斯爆炸机理,对管内瓦斯爆炸传播影响因素和火焰加速机理进行了分析,得出了管内瓦斯爆炸传播影响因素和火焰加速机理,影响因素有:管道因素、混合气体的浓度、混合气体的性质、瓦斯在管道中的充填长度、障碍物、点火方式和点火位置、环境条件,不同的影响因素在不同时期和不同状态时起着不同的作用;火焰加速机理有:在气相燃烧理论中的压力波与燃烧阵面相互作用而导致界面不稳定性理论;由火焰产生的前驱冲击波对未燃混合物的加热和压缩的正反馈机理;火焰阵面微分加速机理;火焰阵面湍流加速机理等.在管内瓦斯爆炸传播过程中,火焰传播有多种加速机理,具体哪种机理对瓦斯爆炸传播起主导作用,取决于加速时间、距离长短、管道具体情况等影响因素.

Based on explosion propagation mechanism, the affecting factors and flame acceleration mechanism of methane explosion in duet are analyzed. Affecting factors are obtained： duct factors, methane concentration, mix gas characters, obstacles, ignition method, ignition location and environment condition; four flame acceleration mechanisms of methane explosion in duct are obtained： the instability mechanism induced by the action between combustion front and pressure wave; the positive feedback mechanism of heating and calefaction induced by fore shock wave; the differential acceleration mechanism of flame front; the turbulence acceleration of flame front. During the propagation of methane explosion, which mechanism does act dominantly that is up to time and distance of flame acceleration and particular configuration of duct, namely, the development degree of all mechanism in detail experiment condition is up to the dominant effect of all factors.