Spray Behavior and Atomization Characteristics of High-pressure Gasoline Injector

In direct-injection gasoline engine. the spray of fuel injector plays important roles in improvement of engine performance and reduction of exhaust emissions. This paper presents the spray development processes, spray structure, and atomization characteristics of high-pressure gasoline injector. Global spray structure was visualized using shadowgraph technique. Also, the cross-correlation particle image velocimetry and PDPA system were utilized to obtain the flow and quantitative characteristics of gasoline spray of high-pressure fuel injector. In this investigation, the visualization and experiment of velocity distribution in the spray were performed at 3, 5, and 7MPa of injection pressure under different ambient pressure conditions. Based on the experimental results, the spray behavior of high-pressure gasoline injector such as the spray visualization, spray structure and counter rotating vortex, spray tip penetration, spray width, and velocity vector fields were investigated. In addition, the other spray characteristics were discussed.