Improvement of Atomization Characteristics of Spray by Multi-Hole Nozzle for Pressure Atomized Type Injector

The purpose of this study is to invent high-efficiency atomization enhancement nozzle, which the spray with large spray angle, short liquid core length and small droplet diameter is obtained. In the previous study, the single hole atomization enhancement nozzle, which excellent spray characteristics are obtained at relatively low injection pressure, was developed. In this study, it was investigated about atomization of the spray of the multihole atomization enhancement nozzle invented in this study, and aimed to improve atomization characteristics and to obtain excellent spray characteristics with shorter breakup length, larger spray angle and smaller droplet diameter. The effects of dimensions of the atomization enhancement nozzle such as hole number, the hole diameter, position of the nozzle hole on atomization of the spray and atomization characteristics were investigated. As a result, it was clarified that in case of the multi-hole atomization enhancement nozzle with hole number of N = 4, breakup length becomes short about 70 p.c. and spray angle becomes large about two times, droplets of the spray become considerably small compared with the single hole atomization enhancement nozzle. Atomization characteristics were improved considerably and uniform spray mass flux distributions are obtained by using the multi-hole atomization enhancement nozzle with hole number of N = 4.