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

In order to investigate influence of multi ̄component combustible gases on explosion characteristics of CH4 in fire area of minesꎬ a 20 L multifunctional spherical gas explosion device was used for experiments to collect explosion pressure parameters. Thenꎬ emission spectra of key free radicals OH and CH2O of CH4 explosion were obtained through a digital oscilloscope. Finallyꎬ influence of multi ̄ 中 国 安 全 科 学 学 报 China Safety Science Journal 第30卷 2020年 component combustible gases on explosion characteristics of CH4 was analyzed from macro and micro aspectsꎬ 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 processꎬ they are affected by oxygen content to different degreesꎬ and CH2O∗ꎬ compared with OH∗ꎬ is more susceptible to oxygen content during the process.