C_1～C_4烷烃混合气体热爆燃的简化机理与分析

Reduced mechanism and analysis for thermal deflagration of C_1-C_4 alkane mixture

为了探索油气在受限空间热爆燃发生的化学反应机理,以CHEMICAL4.1为平台,分析了C1-C4烷烃混合气体热爆燃过程的系统温度、主要组分浓度和中间产物生成率的变化规律。通过敏感性分析、生成速率分析和路径分析等方法,简化了C1-C4烷烃混合气体的详细机理,得到了一个包含37种组分、80个基元反应组成的简化机理,并进行了对比验证。在反应机理上印证了气体热爆燃过程存在缓慢氧化、快速氧化和反应平衡3个阶段。发现与超氧化氢和过氧化氢有关的基元反应是热爆燃发生的关键反应,而大量产生的氢基和羟基最终导致了热爆燃的发生。

For studying the chemical mechanism of thermal deflagration of gasoline-air mixture in the confined space, the temperature of the system, the concentration of main components and the genera- tion rate of production in the deflagration process of C1- C4 alkane were simulated with CHEMI- CAL4.1 as a platform. Based on the analysis for the simulated data of the chemical mechanism, three results were obtained as follows. （1）By sensitivity analysis, rate-of-production analysis, path analysis and so on, the detailed oxidation mechanism of C1-C4 alkane was studied, and drew a reduced mech- anism which consisted of 37 species and 80 reactions. The comparison of the two mechanisms was presented. （2） There existed three distinct stages in the thermal deflagration process based on the analysis for the mechanism, namely slow oxidation, rapid oxidation and reaction equilibrium. （3） In the whole chain reaction process, the reactions generating hydroperoxyl and hydrogen peroxide were the key reactions because the hydrogen and hydroxyl groups were largely generated from them so that they induced the deflagration happen finally.