Using the method of moment, a computational study is performed on the chemical mechanism of the formation of soot particles in laminar premixed methanol/ethylene/air flames. The model involves particle inception, coagulation, condensation and heterogeneous surface growth and oxidation. This mechanism involves 101 species and 543 reactions. The simulations of volume fraction and average diameter of the soot particles and mole fraction of intermediate species import for soot formation were conducted for methanol of different mole fractions. Sensitivity analysis on formation/consumption of acetylene and benzene was made. The oxygen atom transfer path in methanol molecules in the process of fuel combustion was also disclosed. The results show that methanol can effectively reduce soot, polycyclic aromatic hydrocarbons which are the precursor of soot, and the precursors of polycyclic aromatic hydrocarbons such as acetylene and propargyl. The oxygen atoms in methanol molecules transfer among methanoyl, formaldehyde, hydroxide radical, formyl, carbon monoxide and carbon dioxide.%利用矩方法研究了层流甲醇/乙烯预混火焰中碳烟颗粒形成的化学反应动力学机理.模型考虑了颗粒的成核、颗粒间的凝结与聚合、气态组分在颗粒表面的生长与氧化过程.整个机理涉及101种组分和543个基元反应.计算了不同甲醇摩尔分数时碳烟粒子体积分数、粒子直径及重要中间组分的摩尔分数,对乙炔和苯的生成/消耗进行了敏感性分析,揭示了甲醇燃烧过程中氧原子的迁移路径.计算结果表明,甲醇能有效地减少碳烟及其前驱体多环芳香烃、多环芳香烃前驱体物质(如乙炔、炔丙基等)的生成量.燃烧过程甲醇中氧原子在甲醇基、甲醛、羟基、甲醛基、一氧化碳和二氧化碳等物质中迁移.
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