Combustion characteristics and exhaust gas emissions of lean mixture ignited by direct diesel fuel injection with internal EGR

摘要

The uniform lean gasoline-air mixture was provided to the diesel engine and was ignited by the direct diesel fuel injection. In this study, the internal EGR is added to this ignition method in order to activate the fuel in the mixture before the ignition. It is confirmed that the lean mixture of air-fuel ratio between 150 and 40 could be ignited and burned by this ignition method when the back pressure of 80 [kPa] is added, and the burning period is shorted by internal EGR. However, as the back pressure increases, NO_x concentration is increased by the high-temperature residual gas.