EGR성층화가 액상분사 LPG엔진의 희박연소에 미치는 영향

Abstract

Stratified EGR (Exhaust Gas Recirculation) achieves not only reductions in NOx emission and fuel consumption but also combustion stability improvement for highly diluted mixture. In this study, the timing and duration of a fast-response solenoid valve installed in the midst of EGR line was controlled to form the axial stratification of EGR within the cylinder. Lean burn of LPG with both stratified and homogeneous EGR was examined in terms of the rate of heat release, combustion stability (or EGR tolerance), fuel consumption and engine-out emissions. Since stratified EGR showed faster combustion and improvement in combustion stability, more EGR amount was admitted and more reduction of NOx emission with less increase in HC emission was attained with stratified EGR than homogeneous EGR.