Abstract
Diesel engines with direct fuel injection systems are up to now the propulsion systems with the highest efficiency in the automotive domain. A major disadvantage of Diesel engines are the high soot emissions which cannot be reduced completely only with engine methods existing nowadays. The main source for soot formation during the combustion is the interaction of liquid fuel with the flame. This effect appears especially in modern direct injection engines where the injection is often split in a pre- and a main injection due to noise reasons and to reduce the exhaust polluants. With this investigations, the fundamental understanding of the interaction from pilot and main injection should be improved and possible solutions to overcome the problem of soot formation should be proposed. The effects of the injection strategy on the combustion process will be investigated using cylinder pressure indication and exhaust gas analysis.
Keywords: diesel engine, direct injection, soot reduction