增氧剂DMC对电喷汽油机排放特性的影响  

Effects of the Oxygenates DMC on the Regulated Exhaust Emissions from an EFI Gasoline Engine

作　　者：董素荣[1] 宋崇林[1] 张延峰[1] 赵昌普[1] 郭振鹏[1] 徐冠鹏[1] 刘文胜[1] 

机构地区：[1]天津大学内燃机燃烧学国家重点实验室

出　　处：《燃烧科学与技术》2005年第4期350-354,共5页Journal of Combustion Science and Technology

基　　金：国家自然科学基金资助项目(50076032);国家重点基础研究发展规划(973)资助项目(2002CB211603).

摘　　要：以90#无铅汽油为基础油,按照50/0、100/0、150/0、200/0(体积分数)的甲基叔丁基醚/汽油混合燃料中的氧含量,配制出相应氧含量的碳酸二甲酯(DMC)/汽油混合燃料,分析研究了不同掺混比例的DMC/汽油混合燃料对电喷汽油机排放特性的影响及三效催化器的净化效率.研究结果表明,在不改变汽油机任何参数的情况下,小负荷时,汽油机燃用DMC/汽油混合燃料,CO和THC排放都有明显改善,尤其当添加比例为1.20/0(体积分数)时,CO和THC排放与基础油相比分别降低约450/0和200/0.然而,在中、高负荷时,随着DMC掺混比的增大,CO和THC排放改善不明显.当添加比例达到4.70/0(体积分数)时,在低速和高速工况下,NOx排放降低约200/0.三效催化器对CO和THC的平均净化效率超过900/0,而对NOx的净化效率相对低一些,仅为300/0.三效催化器的净化效率与DMC的含量和发动机的工作状态有关.According to to the oxygen concentrations in the methyl tertiary butyl ether（ MTBE）/gasoline blended fuels with 5%, 10%, 15% and 20% （ volume percentage） MTBE respectively, dimethyl carbonate （DMC） was mixed into 90# unleaded gasoline. The effects of DMC addition into gasoline on the regulated exhaust emissions from an EFI gasoline engine and catalytic conversion efficiencies were investigated. The experimental results indicate that CO and THC emissions from the EFI gasoline engine to fuel DMC/gasoline mixtures are drastically reduced at low engine load, especially for DMC containing 1.2% （ at the level of 45% and 20%） , while with the increasing DMC concentration in the blended fuels, there is no significant change at the medium and high loads. With the fuel containing 4.7% DMC, NOx emission is decreased by about 20% at low and high engine speeds before the catalytic treatment. The average catalytic conversion efficiencies of CO and THC reaches over 90%, but catalytic conversion rate of NOx only reaches 30%. The efficiency of catalytic converter has relations to the speed, load of the engine and the DMC content in the blended fuels.

关 键 词：电喷汽油机 碳酸二甲酯 增氧剂 催化器 排放污染物 

分 类 号：TK411.71[动力工程及工程热物理—动力机械及工程]