甲醇空气预混层流燃烧的简化化学反应动力学机理

Simplified Chemical Kinetic Mechanism of Premixed Laminar Combustion of Methanol-Air Mixture

基于甲醇氧化的详细反应历程，利用敏感性分析的方法，提出了一个用于描述甲醇空气预混层流燃烧速度的包含18种组分、28步基元反应的简化化学反应动力学机理．研究发现，在甲醇的氧化过程中，甲醇的分解反应及H、OH等自由基的链锁反应具有十分高的敏感性，其中HCO＋M和H＋O2分别是产生H、OH自由基的主要反应．计算结果与实验结果对比表明，该简化机理可以较合理地模拟当量比为0．6～1．2以及不同初始温度下的层流燃烧速度和火焰结构．与详细机理相比，该机理更适合与CFD三维数值模拟软件耦合．

On the basis of the detailed chemical kinetic mechanism of methanol oxidation, the simplified chemical kinetic mechanism of methanol including 18 species and 28-step elementary reaction was presented to describe premixed laminar flame speed with sensitivity analysis. It is found that the methanol oxidation exhibits strong sensitivity to the kinetics of methanol decompo- sition and the chain reaction of radicals such as H and OH, in which HCO＋M and H＋O2 are the main reactions to generate H and OH radicals, respectively. The comparison between the calculated results and experimental data shows that the present simplified mechanism could simulate laminar flame speed and flame structure reasonably in the range of equivalence ratios from 0.6 to 1.2 and at different initial temperatures. Compared with the detailed mechanism, the simplified mechanism is more suitable to coupling with three-dimensional CFD models.