Influence of Fuel Volatility on Evaporation Characteristics of Diesel Sprays in Various Low Temperature and Low Density Surrounding Conditions Like at Early Pilot or Late Post Injections

The diesel spray characteristics in early pilot and late post fuel injections in a constant volume chamber which can create the in-cylinder conditions of a diesel engine were visualized with high speed video. At the early pilot and late post fuel injection, there was a longer penetration of the liquid phase fuel spray as well as slower evaporation. With normal heptane the impingement of liquid spray with early pilot and post fuel injections can be avoided due to a faster evaporation. The penetration of liquid phase fuel spray increases significantly at low IMEP and late post injection conditions with diesel fuel.