In this work, the effect of high injection pressures and ambient gas properties on diesel spray penetration and spreading angle are studied. To this end a multi-hole piezoelectric injector was used, and MIE-Scattering optical technique to visualize the spray. Injection pressures up to 270 MPa were used throughout the experiments. Additionally, the spray behavior going from subsonic to supersonic state was analyzed by controlling the ambient gas speed of sound, promoting in this way supersonic jets. For this purpose, measurements were done using three different ambient gases (SF 6 , CO 2 , and N 2) at isothermal conditions. The results showed that sprays near transonic or in supersonic state had a higher penetration rate than those in subsonic state. Furthermore, among the sprays near transonic or in supersonic state, those with higher Mach number had faster penetration. Differently, within the sprays at subsonic state, no significant variations in spray penetration rate were found, regardless of the difference in the Mach number. Shock waves appearances were pointed out as a possible explanation for the spray penetration variations observed. Finally, a statistical analysis is presented for the spray penetration under isothermal conditions and for each ambient gas.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.