【摘要】 利用KIVA-3V软件模拟了柴油机两种燃烧方式的混合气形成过程中的浓度场和温度场.模拟计算与实验结果表明,在常规柴油机燃烧方式中,燃油边喷边烧,混合气浓度和温度变化很大,导致预混合燃烧和扩散燃烧并存,NOx和碳烟比较高,CO和HC排放很低;利用早喷可以形成浓度场和温度场分层分布的均质混合气,实现均质充量压燃(HCCI)燃烧,碳烟和NOx很低,但CO和未燃烧的燃油排放很高.更多还原

【Abstract】 It simulated the concentration and temperature fields in the process of mixture formation with two combustion modes in a diesel engine by KIVA-3V.The computational simulations and experiments show that in the normal combustion mode,the density and temperature of mixtures change greatly in the combusting sprays so that there are premix combustion and diffusion combustion simultaneously,which results in high NOx and smoke emissions,low CO and HC emissions.Homogeneous charge compression ignition(HCCI) combustion takes place by earlyinjection to form stratified homogeneous mixtures,which results in very low NOx and smoke emissions,high CO and fuel emissions that are not combusted.更多还原