多元可燃气体对CH4爆炸及其自由基发射光谱影响试验

Influence of multi-component combustible gases on explosion characteristics and free radical emission spectrum of CH4

为探究矿井火区多元可燃气体对CH4爆炸特性的影响,采用20 L多功能球形气体爆炸试验装置开展爆炸试验,采集爆炸压力参数;通过数字示波器得到CH4爆炸关键自由基OH*和CH2O*的发射光谱信息;从宏观、微观2方面分别分析多元可燃气体对CH4爆炸特性的影响,并将两者进行关联对比。研究表明:多元可燃气体对CH4爆炸的影响因氧气含量不同呈现不同特征,贫氧状态下多元可燃气体含量的增加对CH4爆炸起到抑制作用,随着氧气含量的增加抑制作用逐渐减弱,最后达到富氧状态时变为促进作用;关键自由基发射光谱的相对强度与其对应的爆炸压力参数变化特征基本一致;不同自由基虽然在参与反应过程中整体变化趋势相同,但是受到氧气含量影响程度不同,相对于OH*而言CH2O*在整个反应过程中更易受到氧气含量的影响。

In order to investigate influence of multi-component combustible gases on explosion characteristics of CH4 in fire area of mines,a 20 L multifunctional spherical gas explosion device was used for experiments to collect explosion pressure parameters.Then,emission spectra of key free radicals OH*and CH2O*of CH4 explosion were obtained through a digital oscilloscope.Finally,influence of multi-component combustible gases on explosion characteristics of CH4 was analyzed from macro and micro aspects,and they were correlated and compared.The research shows that their influence indicates different characteristics due to different oxygen contents.An increase in multi-component combustible gas content under an oxygen-depleted state can inhibit explosion of CH4.But its inhibition effect gradually weakens as oxygen content increases until an oxygen-rich state is reached.Relative intensity of key radical emission spectra is basically consistent with corresponding changes of explosion pressure parameters.Although different radicals have the same change trend in participating in reaction process,they are affected by oxygen content to different degrees,and CH2O*,compared with OH*,is more susceptible to oxygen content during the process.