Paper ID ICLASS06-011 Practical Study on High-Dispersion Atomization Enhancement Nozzle (Effects of Ambient Pressures on Atomization of Spray and Application to Actual Diesel Nozzle)

The purpose of this study is to develop the atomization enhancement nozzle, which is able to obtain the spray with high-dispersion and high-penetration. Moreover, it is to apply the atomization enhancement nozzle to an actual Diesel injector, and it is to improve the spray characteristics of a direct injection Diesel nozzle. In this paper, the effects of the ambient pressures on atomization of the spray of the atomization enhancement nozzle and the effects on atomization of the spray at the intermittent injection were investigated. Moreover, the correlation of the atomization characteristics between an enlarged nozzle and an actual size nozzle were investigated. The results show that the atomization enhancement nozzle developed in this study was obtained the excellent spray and the spray characteristics, which the breakup length is short, the spray angle is large and the droplet diameter is small, and atomization of the spray and the spray characteristics were considerably improved. Moreover, it was clarified that the spread of the spray of this atomization enhancement nozzle at the high-ambient pressure condition is larger than the atmospheric pressure condition and this nozzle is able to obtain the excellent spray with large spray angle under the high-ambient pressure condition. Although the spray tip penetration of the atomization enhancement nozzle is short compared with one of the single hole nozzle, the spread of the spray of the atomization enhancement nozzle is larger than one of the single hole nozzle at the intermittent injection. It can be seen that atomization of the spray is enhanced considerably at the intermittent injection. Furthermore, approximate correlations between the enlarged nozzle and the actual size nozzle were obtained.