Abstract
Abstract:
EGR (Exhaust Gas Recirculation) system is widely used to reduce NOx emissions, especially for gasoline DI engines where stratified charge combustion is conducted to improve the thermal efficiency. However, the effect of EGR on stratified charge combustion is not well clarified. In this study, an experimental apparatus that can realize simplified charge stratification fields is employed to test combustion characteristics. Two kinds of dilution gases, N2 and CO2, were added to examine the combustion characteristics in both the homogeneous and the stratified charge combustion. As a result, a difference in combustion characteristics was found depending not only on the properties of the diluents, but also on turbulence intensity.