汽油机缸内直喷的关键技术和发展现状

Key Technology and Developing Status of Direct Fuel Injection in Gasoline Engine

讨论了缸内直喷发动机的优缺点和当前对该种发动机提出的要求，认为缸内直喷技术的关键是掌握和控制好混合气浓度在空间的分布和随时间的变化。其控制是在一定的喷油、点火控制策略下靠燃油喷射系统与缸内流场的合理匹配实现的。阐述了缸内直喷对上述两个方面提出的要求，并讨论了发动机排放及其解决方法。

The advantages and disadvantages of direct fuel injection in the cylinder and the requirements for the engine at present time are discussed.It is noted the key factor in direct fuel injection in the cylinder is to master and control perfectly the mixture density spreading in cylinder and the variables with time change.Its control can be realized by reasonable match of fuel injection system and flow field inside the cylinder under the conditions of determined fuel injection and ignition control.The requirements of two above－mentioned conditions inquired by direct fuel injection in cylinder are described,the engine emissions and their solutions are discussed also.