掺烧乙醇对柴油机均质压燃影响的机理研究  

Study on the influence mechanism of blending ethanol on diesel homogeneous charge compression ignition combustion

作　　者：莫春兰[1] 许明疆[1] 罗廉[1] 黄豪中[1] 耿葵花[1] 

机构地区：[1]广西大学机械工程学院,广西南宁530004

出　　处：《广西大学学报（自然科学版）》2010年第5期762-765,781,共5页Journal of Guangxi University（Natural Science Edition）

基　　金：广西自然科学基金资助项目(桂科青0991008-4A);广西大学博士启动基金项目(X091012);广西制造系统与先进制造技术重点实验室项目(桂科能07109008_004_Z)

摘　　要：研究纯柴油和以体积计90%柴油掺烧10%乙醇双燃料的化学动力学反应机理,分析乙醇加入对柴油均质压缩燃烧的重要物种、自由基和关键反应的影响。计算结果表明,乙醇在一定程度上抑制了柴油的低温反应,低温放热率峰值降低,负温度系数区域延长,高温阶段放热时间滞后且放热率峰值迅速增加。H2O2、HO2和OH是反应中生成的重要自由基,乙醇的加入使得这些自由基生成量减少且生成滞后,从而导致高温反应滞后。与纯柴油相比,掺燃乙醇使得反应产生的醛类物质数量减少,其中甲醛减少最为明显,其次为乙醛,而且对于常规排放物CO有所改善。On the basis of the detailed chemical kinetic mechanism of diesel and ethanol/diesel blends,the influences of important species,free radicals and the key reactions on homogeneous charge compression ignition（HCCI） engine fueled with ethanol/diesel blends and conventional diesel were compared.Calculation results showed that blending ethanol in diesel oil,the peak values of heat release rate（governed by low temperature reactions（LTR）） decreased;the negative temperature coefficient region（NTCR） prolonged;the peak values of heat release rate（governed by high temperature reactions（HTR）） increased rapidly and the timing delayed obviously.Comparing with diesel,ethanol/diesel blends made the concentration of H2O2,HO2 and OH key radicals decreased and the existent time were longer,which caused HCCI high temperature reactions delayed.In addition,CH2O,CH3CHO and CO emission decreased,especially CH2O decreased obviously.

关 键 词：柴油/乙醇 均质压燃 放热率 排放 

分 类 号：TK421[动力工程及工程热物理—动力机械及工程]