多元混合气体对CH_(4)爆炸影响的反应动力学模拟

Reaction kinetic simulation of the effect of multi-component mixed gas on CH_(4) explosion

为深入研究多元混合气体对CH_(4)爆炸的影响和作用机理,选取C_(2)H_(6),C_(2)H_(4),CO,H_(2)典型可燃气体,采用CHEMKIN软件构建零维封闭均相反应器模型,研究其对CH_(4)爆炸反应过程的影响,模拟分析以CO为主导的混合气体对CH_(4)最大爆炸压力、最大爆炸温度和爆炸过程中关键自由基(H,O,OH)的影响,同时对H+OH自由基最大体积分数变化规律进行分析,并与理论当量状态下各单一气体对CH_(4)爆炸过程的影响规律作对比。结果表明:混合气体的添加对CH_(4)最大爆炸压力和最大爆炸温度有明显促进作用;爆炸过程中H自由基最大体积分数持续增加,O和OH自由基最大体积分数变化与CH_(4)体积分数有关;多元混合气体对CH_(4)的最大爆炸压力和最大爆炸温度影响与单一H2或CO对其影响规律相似,对关键自由基(H,O,OH)的影响规律与CO更为接近。通过敏感性分析获得了影响CH_(4)爆炸过程的关键反应。

In order to deeply study the influence of multi-component mixed gas on CH_(4) explosion and to analyze its mechanism,C_(2)H_(6),C_(2)H_(4),CO,H_(2) were selected as typical combustible gases,using the CHEMKIN software,a zero-dimensional closed homogeneous reactor model was built to study the four types of mixture effect of gas on CH_(4) explosion reaction process.The maximum explosion pressure and temperature of CO-dominated gas mixture to CH_(4) and the key free radicals(H,O,OH)during the explosion were simulated and analyzed.The change law of the peak content of free radical H+OH was also analyzed,and compared with the influence law of each single gas on the CH_(4) explosion process in the theoretical equivalent state.The results showed that:The addition of mixed gas could obviously promote the maximum explosion pressure and temperature of CH_(4),the maximum concentration of H radical increased continuously during the explosion,and the change of the maximum concentration of O and OH free radicals was related to the concentration of CH_(4).Compared with a single gas,it was found that the influence on the maximum explosion pressure and temperature of methane was similar to that of a single gas of H2 and CO,and the influence of key free radicals(H,O,OH)was closer to that of CO.The key reactions affecting the explosion process of CH_(4) were obtained by sensitivity analysis.