서지주요정보
가솔린 직접분사식 4행정 엔진의 성능개선에 관한 연구 = A study on the development of gasoline direct injection 4-stroke engine
서명 / 저자 가솔린 직접분사식 4행정 엔진의 성능개선에 관한 연구 = A study on the development of gasoline direct injection 4-stroke engine / 이용표.
저자명 이용표 ; Lee, Yong-Pyo
발행사항 [대전 : 한국과학기술원, 1999].
Online Access 원문보기 원문인쇄

소장정보

등록번호

8009613

소장위치/청구기호

학술문화관(문화관) 보존서고

DME 99008

SMS전송

도서상태

이용가능

대출가능

반납예정일

초록정보

The effects of injection systems and combustion chamber shapes on the GDI (Gasoline Direct Injection) engine combustion have been studied. Two types of 2-phase injector (or air-assisted fuel injector), which is one of the most important element for the GDI engines, were developed. Their spray characteristics related with operation and atomization, and combustion performance characteristics were investigated. Each of them produced finely atomized spray characterized with 14.9μm and about 20μm, respectively, in SMD. The structure of spray in terms of mass concentration and SMD distribution was also investigated. Atomization performance was tested as a function of design variables and operating parameters. One of them exhibited stable behavior at various speeds up to 6,000rpm. In the combustion experiment of 2-phase injector using RCEM (Rapid Compression and Expansion Machine) and GDI engine, pressure data, photographs and emission data were taken at several conditions with various ignition, injection, flow, temperature, and engine speeds. Spark plug must be located in the region of spray for stratified combustion. Finding the proper injection timing was important for the lean mixture combustion. Swirl did not give beneficial effect on stratification process. Intake temperature and cylinder wall temperature were not dominant factors on combustion performance. It was hard to achieve stratification at high engine speeds since the intake flow velocity was increased. A deflector installed on the injector nozzle tip could control spray direction. Flame speed of stratified mixture was observed to be faster than that of pre-mixed mixture. Combustion performance of the GDI engine was compared with conventional PFI (Port Fuel Injection) engine in terms of imep and emissions. As a result, the lean limit of GDI engine using 2-phase injector was extended to Φ = 0.65 compared to Φ = 0.75, in PFI engine. A single-cylinder optical engine was constructed to observe DISC (Direct Injection Stratified Charge) processes. Combustion performance of GDI engine using swirl injector was examined while it was operated with six-shapes of combustion chamber conditions. Two injector positions and three piston shapes were used. When GDI engine was operated at the early injection condition, the evident differences of combustion performance in terms of imep with regard to the combustion chamber shapes could be observed. Additionally, film combustion phenomenon around the end of combustion process was observed in the optical engine. The difference of wetted fuel amount could be regarded as a reason for this imep variation. There was a strong negative correlation between the imep value and the wetted fuel amount. At partial load conditions, the center injection case was better than the case of side injection and stable combustion can be obtained under very lean condition with air fuel ratios exceeding 36.

서지기타정보

서지기타정보
청구기호 {DME 99008
형태사항 xviii, 176 p. : 삽도 ; 26 cm
언어 한국어
일반주기 저자명의 영문표기 : Yong-Pyo Lee
지도교수의 한글표기 : 최상민
지도교수의 영문표기 : Sang-Min Choi
수록 잡지명 : "A Study of Two-Phase Injector Performance for Direct-Injection Stratified-Charge Engines". Atomization and Sprays,, vol.8, pp. 199-215 (1998)
학위논문 학위논문(박사) - 한국과학기술원 : 기계공학과,
서지주기 참고문헌 : p. 167-176
주제 가솔린 직접분사
2유체분사기
분무
연소실
연료점착
GDI
2-Phase injector
Spray
Combustion chamber
Wetting
QR CODE qr code