Abstract:

To study the coupling oscillation characteristics of the explosion flame and pressure of premixed gas, a transparent plexiglass explosive pipeline experimental platform with dimensions of 80 mm×80 mm×1000 mm was built. The results show that the coupling oscillation of CH₄/O₂/N₂ premixed gas explosion flame and pressure will be affected under the condition that the oxygen concentration E and the detonation area ratio S change. When the oxygen concentration E changes from 0.21 to 0.40, the flame propagation time decreases gradually, the flame structure evolves dynamically, the oscillation phenomenon in the later flame is more obvious, and the oscillation enhancement phenomenon also exists in the later stage of the measured pressure curve. When the detonation area changes from 0.125 to 1.000, the pressure curves of S=0.125 and S=0.250 under E=0.21 conditions are different from those of other working conditions, a higher pressure peak is observed, and new pressure peaks appear in S=0.125 under E=0.30 conditions, and the peak pressure of E=0.30 and E=0.40 two kinds of working conditions decreases gradually, the oscillation amplitude in the later stage of pressure is related to the explosion area ratio.

Key words: premixed gas, explosion, flame, pressure, oscillation

摘要：

为研究预混气体爆炸火焰和压力的耦合振荡特性，自行搭建了尺寸为80 mm×80 mm×1000 mm透明有机玻璃爆炸管道实验平台。实验结果表明，在氧气浓度E和泄爆面积比S变化的条件下，会对CH₄/O₂/N₂预混气体爆炸火焰与压力的耦合振荡产生影响。当氧气浓度E从0.21到0.40变化时，火焰传播时间逐渐缩短，火焰结构发生动态演变，火焰后期的振荡现象愈加明显，同时测到的压力曲线在后期也存在振荡增强现象；当泄爆面积比S从0.125到1.000变化时，E=0.21工况下S=0.125和S=0.250两个工况与其他工况的压力曲线有所不同，出现了一个更高的压力峰值，E=0.30工况下S=0.125也出现了新的压力峰值，E=0.30和E=0.40两种工况的压力峰值都逐渐减小，压力后期的振荡幅值与泄爆面积比有关。

关键词: 预混气体, 爆炸, 火焰, 压力, 振荡