摘要
为深入探究废气再循环技术(EGR)对柴油机颗粒形成的作用机理,运用拉曼光谱(Raman)、热重分析(TG)等试验方法研究EGR率对排放颗粒的微晶结构及氧化特性的影响,探明颗粒的化学异相性、石墨化程度、平均微晶尺寸、CC原子键距、活化能等参数的变化规律。结果表明:随EGR率的增加,D1峰的半高宽逐渐增大,化学异相性增强;ID1/IG、ID3/IG比值逐渐增加,与EGR0%颗粒相比,EGR30%颗粒的ID1/IG、ID3/IG分别增加了12.9%、12.1%,颗粒的有序石墨结构含量减少,无定形碳含量增加,石墨化程度降低;颗粒的平均微晶尺寸逐渐减小。颗粒的活化能随EGR率的增加而有所减小,与EGR0%颗粒相比,EGR30%颗粒的活化能减小3.6%,表明引入废气提高了柴油机排放颗粒的氧化活性。
In order to explore the mechanism of EGR on the formation of diesel engine particles,the effects of different EGR rates on the microcrystalline structure and oxidation characteristics of particulate matters were analyzed by means of Raman spectroscopy(Raman)and thermogravimetric analysis(TG).The laws of several parameters were clarified,including the chemical heterogeneity,graphitization degree,average crystallite size,bond length of CC atoms,and activation energy.The results showed that the width at half of D1 peak increased gradually and the chemical heterogeneity of particulate matters enhanced with the increase of EGR rate.The ratios of ID1/IG and ID3/IG gradually increased,which increased by 12.9%and 12.1%respectively for EGR30%.The ordered graphite structure reduced,the amorphous carbon increased,and the graphitization degree weakened.In addition,the average crystallite size and activation energy of particulate matters both decreased.The activation energy of EGR30%decreased by 3.6%,which indicated that EGR could improve the oxidation activity of particulate matters.
作者
瞿磊
王忠
刘帅
谢纬安
QU Lei;WANG Zhong;LIU Shuai;XIE Weian(School of Automotive and Traffic Engineering,Nantong Vocational University,Nantong 226007,China;School of Automobile and Traffic Engineering,Jiangsu University,Zhenjiang 212013,China)
出处
《车用发动机》
北大核心
2020年第5期55-60,共6页
Vehicle Engine
基金
江苏省高等学校自然科学研究面上项目(18KJD470005)
南通市市级科技计划项目(JCZ18029)
南通职业大学校级立项项目(17ZK02)。
关键词
颗粒
柴油机
废气再循环
微晶结构
氧化
particulate matter
diesel engine
exhaust gas recirculation(EGR)
graphitization
oxidation