Abstract
Keywords - Evaporation, multicomponent fuel, GDI, CFD, KIVA-3V
Abstract - The direct injection of gasoline is an effective method to minimize the fuel consumption of gasoline engines and thus to reach the limits for CO2-emissions in 2008 and 2012. The biggest potential for fuel consumption reduction is during unthrottled, part load conditions where a locally homogeneous and ignitable mixture around the spark plug is created. But a complicated and cost intensive exhaust gas aftertreatment and the need for desulfurized fuels increase the complexity of the system.
The homogenous injection mode ensures the use of conventional catalytic converters and leads to a higher specific power as a result of higher compression ratios. Standard fuels can be used and ensure a world wide application possibility.
In this study an multi-hole nozzle on a piezoelectrically controlled research injector was used to evaluate the potential of gasoline direct injection under high pressure conditions up to 30
MPa. The optical measurements take place in an optically accessible rapid compression machine while the injector allows a direct influence on the opening characteristic. In order to achieve a good comparability with the calculations, the experiments were accomplished with isooctane and conventional gasoline. The experimental results were used to calibrate the accompanied
KIVA-3V CFD-calculations, which permit a detailed insight into the mixture formation processes.
The aim of this study is an analysis of the potential of the high pressure gasoline injection in combination with multi-hole nozzles using experiments in conjunction with CFD-calculations.
The emphasis of the analysis is a comparison between isooctane and commercial gasoline fuel and validation of a recently developed multicomponent fuel-model.