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저압 EGR 시스템을 이용한 V6 3.0ℓ엔진의 연비 최적화 개발
이해욱(Haewook Lee),조청훈(Chunghoon Jo),남기훈(Kihoon Nam),이세영(Seyoung Lee),이은현(Eunhyun Lee) 한국자동차공학회 2011 한국자동차공학회 학술대회 및 전시회 Vol.2011 No.11
As the markets require more environmentally friendly and high fuel consumption vehicle, we have to satisfy bilateral target. Though many new after-treatment techniques like LNT, SCR are investigated to meet both strong emission regulations and low fuel consumption, high cost of these techniques should be solved to adopt widely. This paper describes how to optimize the dual loop EGR as a tool to reduce CO2 emission of a HSDI diesel engine in the passenger car application. Focus is not only on the optimization to obtain the maximum CO2 reduction but also on how to assess and overcome various side effects. As a result of careful optimization, as much as 6% CO2 reduction was achieved by introduction of low pressure EGR loop, maintaining the same boundary conditions as those with high pressure EGR loop only. Not only the dual EGR system but also further improvement was applied such as combustion improvement, friction reduction and many others to achieve as much as 20% total CO2 reduction. The dual loop EGR was proven to be an effective solution to reduce CO2 and therefore it is considered to be one of the core technologies in the passenger diesel applications of Hyundai-Kia Motors to meet the future CO2 regulation.
옵셋-스트립 핀 타입 가솔린 EGR 쿨러의 열 성능에 관한 수치 해석적 연구
이태호(TaeHo Lee),노국현(Kukhyeon Noh),김일환(Ilhwan Kim),이은현(Eunhyun Lee) 한국자동차공학회 2017 한국자동차공학회 부문종합 학술대회 Vol.2017 No.5
Exhaust emission reduction technologies are being developed to deal with stricter emission regulations such as Euro-6’s. Among the exhaust gas reduction technologies, EGR(Exhaust Gas Recirculation) method reduces the nitrogen oxides by putting in the combustion chamber the exhaust gas that includes substance having high heat capacity such as carbon dioxide to reduce the oxygen density and lower the maximum combustion temperature. In the diesel engine, EGR system has been mostly applied, because of excellent de-NOx efficiency compared to the price. In the gasoline engine, EGR system improves the combustion efficiency by reducing the pumping loss, and fuel efficiency by enhancing anti-knocking property. In this study, the simple model of EGR Cooler was applied by two types of offset strip fin models(shell & volume mesh) and three types of turbulence models. The performance analysis in regard to gas mass flowrates was executed and validated by experimental data. The CFD results showed accuracy differences in regard to fin models and turbulence models.
[디젤엔진부문] 배기 재순환(EGR)이 엔진 열부하와 방열에 미치는 영향
이효조(Hyojo Lee),이은현(Eunhyun Lee) 한국자동차공학회 1999 한국자동차공학회 춘 추계 학술대회 논문집 Vol.1999 No.11_1
EGR(Exhaust Gas Recirculation) is an effective measure for the reduction of exhaust emissions but durability of each engine part decrease. In this study, the effects of EGR on engine performance, air fuel ratio, exhaust gas temperature, cylinder metal temperature and heat rejection were investigated in a diesel engine. The results are as follows. With the increase of EGR rate ; 1. The engine performance and the air fuel ratio decrease. 2. The exhaust gas temperature and the cylinder metal temperature increase. 3. The coolant and the oil heat rejection increase.
열변형을 고려한 터보디젤 엔진용 배기매니폴드 플랜지의 설계
김범근(Beomkeun Kim),이은현(Eunhyun Lee) 대한기계학회 2006 대한기계학회 춘추학술대회 Vol.2006 No.6
Thermal deformation of cast iron exhaust manifold for turbo diesel engine is investigated by finite element analysis (FEA). The FE model included the temperature dependent material properties as well as the interactions between exhaust manifold, cylinder head and fasteners. It also considers the sliding behavior of the flanges of exhaust manifold on cylinder head when either expansion or contraction of the exhaust manifold exceeds the fastener pretension. The result of analysis revealed that remarkable thermal deformation along the longitudinal direction. Compressive plastic deformation at high temperature remained tensile stress in manifold and resulted in longitudinal contraction at ambient temperature. The amount of contraction at each fastener position was predicted and compared with experimental results. Analysis revealed that the design of bolt holes of flanges, which allows sliding behavior, reduced the plastic strain range and delayed thermal surface crack.
열변형을 고려한 터보디젤 엔진용 배기매니폴드 플랜지의 설계
김범근(Beonkeun Kim),이은현(Eunhyun Lee),김용수(Yongsu Kim) 한국자동차공학회 2006 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
Thermal deformation of cast iron exhaust manifold for turbo diesel engine is investigated by finite element analysis (FEA). The FE model included the temperature dependent material properties as well as the interactions between exhaust manifold, cylinder head and fasteners. It also considers the sliding behavior of the flanges of exhaust manifold on cylinder head when either expansion or contraction of the exhaust manifold exceeds the fastener pretension. The result of analysis revealed that remarkable thermal deformation along the longitudinal direction. Compressive plastic deformation at high temperature remained tensile stress in manifold and resulted in longitudinal contraction at ambient temperature. The amount of contraction at each fastener position was predicted and compared with experimental results. Analysis revealed that the design of bolt holes of flanges, which allows sliding behavior, reduced the plastic strain range and delayed thermal surface crack.