CAJ | 학술논문

机油稀释现象是发动机常见的试验表象之一，尤其是增压缸内直喷汽油发动机，机油稀释较明显。机油发生稀释后会破坏机油使用性能，降低运动粘度，严重时还导致机油压力下降，零部件功能丧失，发动机可靠性下降。主要分析一款1.8L GDI缸内增压直喷发动机产生机油稀释的影响因素进而对机油牌号、机油温度、水温、SOI角度、曲轴箱通风系统、活塞漏气量、喷油器布置方式进行Benchmark分析及优化验证，为改善增压直喷发动机机油稀释现象提供解决方法，机油稀释包括燃油喷射稀释和机油挥发稀释，重点探究的方向是燃油喷射稀释。
궤유희석현상시발동궤상견적시험표상지일，우기시증압항내직분기유발동궤，궤유희석교명현。궤유발생희석후회파배궤유사용성능，강저운동점도，엄중시환도치궤유압력하강，령부건공능상실，발동궤가고성하강。주요분석일관1.8L GDI항내증압직분발동궤산생궤유희석적영향인소진이대궤유패호、궤유온도、수온、SOI각도、곡축상통풍계통、활새루기량、분유기포치방식진행Benchmark분석급우화험증，위개선증압직분발동궤궤유희석현상제공해결방법，궤유희석포괄연유분사희석화궤유휘발희석，중점탐구적방향시연유분사희석。
Oil dilution is one of the usual phenomena that happen during engine test,and for TDI gasoline engine that phenomenon is more obvious than that of NA engine. Oil dilution could disable oil from its nor-mal functions and lower its dynamic viscosity; in worse cases that would cause decrease of oil pressure, failure of moving parts and drop of engine's reliability. In this paper factors having influence on oil dilution of one TDI engine with a displacement of 1.8L have been investigated,and in order to find out methods to solve that oil dilution phenomenon benchmark analysis and optimization variation have been done with oil type,oil temperature,coolant temperature,SOI angle,crankcase breath system,piston blow by and lay-out of fuel injector. Oil dilution includes both fuel injection dilution and oil evaporation dilution,in this pa-per fuel injection dilution has been investigated.