应用零维单区模型对生物柴油在发动机燃烧中的化学动力学过程进行了数值模拟,通过分析生物柴油在内燃机边界条件下燃烧氧化过程的关键基元反应、关键中间产物的生成速率(ROP)以及重要自由基,总结出了生物柴油燃烧氧化的主要反应路径.生物柴油的燃烧过程经历低温放热和高温放热两个阶段;在低温放热阶段生物柴油燃料主要通过脱氢反应进行消耗,在高温阶段则通过直接裂解和脱氢反应进行消耗,OH自由基无论在低温阶段还是在高温阶段对燃料的脱氢都起到了主导作用.
Numerical simulation on chemical kinetics of engine combustion fueled with biodiesel was performed by using the single-zone model coupled with detailed kinetic model. The main pathway of bio- diesel combustion was obtained by analyzing the process of biodiesel oxidation of key elementary reac- tions, the production rate of key intermediate species and radicals under engine boundary condition. Combustion fueled with biodiesel consists of a low temperature reaction (LTR)heat release period and a high temperature reaction (HTR) heat release period. H2 atom abstraction from biodiesel is the main path of biodiesel consumption in the low temperature stage. At high temperature, biodiesel is mainly consumed by fuel decomposition and H-atom abstractions of fuel.