가솔린 직접 분사식 엔진에서 연료 분사 압력 증가에 따른 연소 및 배기 배출물 특성

• Published in: 한국분무공학회지 Vol. 22; no. 1; pp. 1 - 7
• Main Authors: 이준순, Junsun Lee, 이용규, Yonggyu Lee
• Format: Journal Article
• Language: Korean
• Published: 한국분무공학회 31.03.2017
• Subjects: Combustion duration(연소기간); Exhaust gas(배기가스); Fuel injection pressure(연료 분사 압력); Gasoline direct injection engine(가솔린 직접 분사식 엔진); Particle number(입자 수); Particle size distribution(입경 분포); Particulate matter(입자상 물질); 기계공학
• ISSN: 1226-2277; 2288-9051
• DOI: 10.15435/JILASSKR.2017.22.1.1

Recently, Performance and fuel efficiency of gasoline engines have been improved by adopting direct injection (DI) system instead of port fuel injection (PFI) system. However, injecting gasoline fuel directly into the cylinder significantly reduces the time available for mixing and evaporation. Consequently, particulate matters(PM) emissions increase. Moreover, as the emission regulations are getting more stringent, not only the mass but also the total number of PM should be reduced to satisfy the Euro VI regulations. Increasing the fuel injection pressure is one of the methods to meet this challenge. In this study, the effects of increased fuel injection pressures on combustion and emission characteristics were experimentally examined at several part load conditions in a 1.6 liter commercial gasoline direct injection engine. The main combustion durations decreased about 2~3° in crank angle base by increasing the fuel injection pressure due to enhanced air-fuel mixing characteristics. The exhaust emissions and number concentration distributions of PM with particle sizes were also compared. Due to enhanced combustion characteristics, THC emissions decreased, whereas NOx emissions increased. Also, the number concentrations of PM, larger than 10 nm, also significantly decreased.