汽车专业英语课件(宋进桂)Chapter 2-7

Ultra-lean Combustion Mode. Under most normal driving
Chapter 2 Internal Combustion Engine 2.7 Gasoline direct injection
Two main operating modes of Volkswagen AG's fuel stratified injection (FSI) which uses more operating modes and FSI’s fuel-saving potential is shown in Figure 2-16. A typical pulse injection system with direct injection is given in Fig.2-17.
Chapter 2 Internal Combustion Engine 2.7 Gasoline direct injection
conditions, up to speeds of 120 km/h, the Mitsubishi GDI engine operates in ultra-lean combustion mode, resulting in less fuel consumption. In this mode, fuel injection occurs at the latter stage of the compression stroke and ignition occurs at an ultra-lean air-fuel ratio of 30-40. This operating mode is also called as stratified-charge mode. Superior Output Mode. When the GDI engine is operating with higher loads or at higher speeds, fuel injection takes place during the intake stroke. This optimizes combustion by ensuring a homogeneous, cooler air-fuel mixture which minimizes the possibility of engine knocking. This mode is also called as homogeneous-charge mode.
ultra-lean
deploy homogeneous stratify
['ʌltrə'li:n]
[di'plɔi] [ֽhɔmə'ʤi:njəs] ['stræ tifai]
a.极端稀薄的，超稀薄
v.展开，部署 a.相似的，均匀的 a. (使)成层，（使）分层
Chapter 2 Internal Combustion Engine 2.7 Gasoline direct injection
Chapter 2 Internal Combustion Engine 2.7 Gasoline direct injection
New Words
drastic response efficiency
['dræ stik] [ri'spɔns] [i'fiʃənsi]
a.剧烈的，猛烈的 n.反应，响应 n.效率，效能，有效性
[veəri'ei∫ən] ['səulinɔid] ['ʃʌtɔ:f] ['enədʒaiz]
n.变化，变更，变种，变调 n.螺线管，电磁线圈[铁，阀，开关] n.中断，切断，关闭al Combustion Engine 2.8 Diesel Fuel Injection System
Fuel Filter. Diesel fuel must be kept clean to avoid injector system trouble. Very small particles are enough to clog injector nozzles. Diesel fuel systems typically use one or more filters to trap dirt and other deposits. Injection Pump. Due to the high compression (around 22:1) used in diesel engines, the diesel injection pump must be capable of producing high pressures. There are a number of injection pump designs. The most commonly used automobile and light truck diesel injection pumps are classified as inline or distributor. The inline injection pump（Figure 12-18） uses a separate cylinder plunger-cam unit （Fig.2-20）for each cylinder. These units are contained in a straight row in a common housing.
2.8.1 Conventional System Typical diesel system components include the fuel tank, fuel pump, fuel filter, injection pump, injectors, and the necessary fuel lines (Fig.2-18). The system in Fig.2-19 is typical of newer systems that utilize a computercontrolled electronic fuel injection pump.
Although MPI provides a drastic improvement in response and combustion quality, it is still limited due to fuel and air mixing prior to entering the cylinder. To further increase throttle response and combustion efficiency, while lowering fuel consumption and increasing output, systems may use direct injection. Gasoline direct injection engines are engineered to inject the gasoline directly into the cylinder in a manner similar to diesel direct injection engines (Fig.2-14). Direct injection is designed to get better fuel economy. This is accomplished by enabling combustion of an ultra-lean mixture under many operating conditions. Direct injection is also designed to allow higher compression ratios, delivering higher performance with lower fuel consumption. Currently, direct injection gasoline engines are being deployed throughout the world in passenger cars.
Chapter 2 Internal Combustion Engine 2.7 Gasoline direct injection
A variety of air-fuel mixtures can be created according to changes in the fuel injection timing. The GDI engine provides both lower fuel consumption and higher output. This is achieved with the use of two combustion modes. These two modes are represented in Figure 215.
Chapter 2 Internal Combustion Engine 2.7 Gasoline direct injection
Fig.2-17 Gasoline direct injection system
Chapter 2 Internal Combustion Engine
2.8 Diesel Fuel Injection System
Chapter 2 Internal Combustion Engine
2.8 Diesel Fuel Injection System
Fig2-18 A conventional diesel fuel injection system
Chapter 2 Internal Combustion Engine 2.8 Diesel Fuel Injection System
New Words
particle