Evaluation of EGR applicability for NOx reduction in lean-burn LPG direct injection engine

초희박 LPG 직접분사식 엔진에서 질소산화물 저감을 위한 배기재순환 적용성 평가

Park, Cheolwoong;Cho, Seehyeon;Kim, Taeyoung;Cho, Gyubaek;Lee, Janghee

  • Received : 2015.04.16
  • Accepted : 2015.08.25
  • Published : 2015.08.31


In order to keep the competitiveness of LPG fuel for transportation fuel, the difference in fuel consumption with gasoline and cost for an aftertreatment system should be reduced with continuous development of technology for LPG engine. In the present study, spray-guided type direct injection combustion system, whose configuration is composed of direct injector in the vicinity of spark plug, was employed to realize stable lean combustion. A certain level of nitrogen oxides($NO_x$) emits due to a locally rich mixture regions in the stratified mixture. With the application of EGR system for the reduction of $NO_x$, 15% of $NO_x$ reduction was achieved whereas fuel consumption and hydrocarbon emission increased. By the application of EGR, the combustion speed reduced especially appeared at initial flame development period and peak heat release rates and increasing rates for heat release rate decreased as EGR rate increased due to the dilution effect of intake air.


LPG engine;Lean combustion;Spray-guided type direct injection system;Exhaust gas recirculation


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Grant : 저연비 복합연료 신형식 엔진 기술 개발 (1/3)