影响汽车甲醇发动机燃烧特性的敏感因素分析

Analysis of Sensitive Factors Affecting Combustion Characteristics of Automobile Methanol Engine

针对影响汽车甲醇发动机燃烧特性的敏感因素,研究不同发动机转速、进气温度和过量空气系数对其燃烧特性的影响。建立甲醇发动机燃烧室模型,利用AVL-Fire仿真分析不同因素下甲醇发动机的气缸压力、缸内温度和放热率的变化规律,对比不同因素下最高气缸压力、缸内温度和放热率峰值的变化程度。结果表明,过量空气系数对甲醇发动机的最高气缸压力、缸内温度和放热率峰值的影响程度最大。3个分析因素中,甲醇发动机燃烧特性受过量空气系数的影响最为敏感。

Aiming at the sensitive factors affecting the combustion characteristics of automobile methanol engines,the effects of different engine speeds,intake air temperatures and excess air coefficients on their combustion characteristics are studied.Establish a methanol engine combustion chamber model,use AVL-Fire to simulate the changes of cylinder pressure,in-cylinder temperature and heat release rate of methanol engine under different factors,and compare the degree of change of the maximum cylinder pressure,in-cylinder temperature and peak heat release rate under different factors.The results show that the excess air coefficient has the greatest influence on the maximum cylinder pressure,in-cylinder temperature and peak heat release rate of the methanol engine.Among the three analysis factors,the combustion characteristics of the methanol engine are most sensitive to the effect of the excess air coefficient.