An experimental study of spray characteristics of a diesel and analyzing of fuel dripping phenomenon

In order to study the spray characteristics of a certain type of a domestic injector, experimental study on its macroscopic spray characteristics was carried out with and without environmental pressure respectively by using high-speed photography technology. Macroscopic spray forms with different injection pressure and environmental pressure were obtained. Based on this, a fuel dripping phenomenon at the end of the spray was captured by using a telephoto macro lens and the causes of the dripping were analyzed. The study indicates that increasing either injection pressure or environmental pressure can increase spray cone angle evidently and can then expand the scope of spray field in combustion chamber, which is conducive to air-fuel mixture. Spray cone angle against spray process shows a double-peak shape. And slow seating of solenoid valve core resulting in slow close of injection is one of the causes of fuel dripping phenomenon. ©, 2015, Chinese Society for Internal Combustion Engines. All right reserved.