基于远后喷的DPF再生技术对发动机机油及抗拉缸性能研究  

Effect of DPF Regeneration Based on In-cylinder Post Fuel Injection Technology on Lubrication Oil and Liner Scuffing

作　　者：刘军 郭雪飞 黄国龙 郭灵燕 冯海娣 武敬 LIU Jun;GUO Xuefei;HUANG Guolong;GUO Lingyan;FENG Haidi;WU Jing(State Key Laboratory of Engine Reliability,Weifang 261061,China;Weichai Power Co.,Ltd.,Weifang 261061,China)

机构地区：[1]内燃机可靠性国家重点实验室,潍坊261061 [2]潍柴动力股份有限公司,潍坊261061

出　　处：《内燃机工程》2018年第5期80-85,共6页Chinese Internal Combustion Engine Engineering

基　　金：国家重点研发计划(2016YFD0700703)~~

摘　　要：采用缸内远后喷技术进行柴油机颗粒过滤器(diesel particulate filter,DPF)再生。通过配制不同质量比的柴油和机油,分析机油黏度和闪点的变化趋势。采用特定循环进行机油老化验证和机油稀释试验,利用热重分析仪研究柴油和机油的挥发特性,并在机油黏度下限进行极限拉缸和高温拉缸试验。试验结果表明:随着燃油稀释率的增加,机油黏度和闪点呈下降趋势,且黏度到达下限值时,燃油稀释率为7%左右。远后喷不会引起柴油的不完全燃烧,也不会导致机油中烟炱(soot)的增加。随着再生次数的增加,机油黏度下降较快,至再生50次后,黏度未达到下限值。热重曲线可以看出柴油和机油的挥发温度差别较大,含7%柴油的机油在120℃会有少量挥发。最小间隙拉缸和高温拉缸试验完成后拆检缸套、活塞环、活塞等主要摩擦副,未出现异常磨损,发动机出现拉缸的风险较小。Diesel particulate filter(DPF)regeneration was carried out by in-cylinder fuel post-injection technology.The changed trend of oil viscosity and flash point were analyzed with different mass ratios between oil and diesel.Oil aging and fuel dilution were also researched by a special circle test.The volatilizations of diesel and oil were studied by thermo gravimetric analyzer.With the oil of the lower limit of viscosity,a liner scuffing test with the minimum clearance between liner and piston rings and a liner scuffing test at high temperature were performed.The results show that oil viscosity and flash point both decline following the growth of fuel dilution ratio.The fuel dilution ratio is 7%when the oil viscosity reaches the lower limit.The post-injection technology will not cause incomplete combustion or soot increase.With the increase of regeneration times,the oil viscosity decreases rapidly,and after 50 times of regeneration,the oil viscosity does not reach the lower limit.The thermo gravimetric curve demonstrates that the volatilizing temperatures of diesel and oil are quite different.Oil with 7%fuel will volatilize slightly at 120℃.The engine tier down inspection after the two liner scuffing tests shows that the main friction parts like cylinder liner,piston and piston rings do not appear abnormal wear,indicating that the engine has a low risk of liner scuffing.

关 键 词：柴油机 再生 机油老化 燃油稀释 拉缸 

分 类 号：TK421[动力工程及工程热物理—动力机械及工程]