• 에너지공학
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• 제19권4호
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• pp.246-250
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• 2010

12 리터급 경유엔진을 개조한 LNG 혼소엔진에 대해 출력, 연비 및 배출가스등의 성능을 평가하였으며 이를 바탕으로 LNG혼소 화물 자동차의 경제성을 분석하였다. 출력은 경유엔진에 비해 5% 정도 낮은 수준으로 평가되었으며 엔진효율은 경유의 경우 37.4%, LNG혼소의 경우 35.9%로 경유엔진의 경우가 다소 높게 나타났다. 배출가스는 탄화수소를 제외하고 PM, NOx, CO 및 $CO_2$는 LNG 혼소의 경우가 낮은 특성을 보였다. 경제성 비교를 위해 연료비용과 환경비용 관점에서 각각 분석하였으며 유가보조금 및 할인을고려할 경우에도 LNG 혼소 화물차의 경제성이 있는 것으로 분석되었다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.554-559
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• 2008

Most of vehicle manufacturers have applied exhaust gas recirculation (EGR) system to the development of diesel engines in order to obtain the high thermal efficiency without $NO_X$ and Particulate Matter (PM) emitted from the engine. EGR system, which reflow a cooled exhaust gas from vehicles burning diesel as fuel to a combustion chamber of engine, has been used to solve this problem. In order to confirm the safety of the EGR system, finite element analysis was carried out. The safety of EGR system against temperature variation in the shell and tubes was evaluated through the thermal and structural analysis, and the modal analysis using ANSYS was also performed. Finally, the performance of EGR system was verified through the experiment and numerical simulation using effectiveness-NTU method. Program for the estimation of the heat exchange efficiency of the EGR system with regard to the dimpled tube shape was developed.

• 대한기계학회논문집B
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• 제36권2호
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• pp.217-224
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• 2012

비도로용 차량의 경우 대부분 디젤엔진을 사용하여 엔진의 특성상 PM과 NOx의 배출이 많은 단점이 있다. 승용 및 상용 디젤 차량의 경우 CRDI 및 후처리 장치를 적용하였고 후처리 장치로 DOC/DPF를 장착함으로써 PM은 약 90% 이상 저감 가능하다. 상반관계인 NOx는 EGR 사용을 통해 1차적으로 NOx 배출량을 감소시키고 LNT, LNC, Urea-SCR 등의 DeNOx 시스템으로 NOx의 배출량을 보다 현저히 저감시켜 배기규제를 만족시키고 있다. 본 연구에서는 tier 4 interim 배기규제를 만족하기 위해 56kW급 오프로드 차량으로 연구를 진행하였다. NOx의 감소를 위해 WGT와 전자 제어방식의 HPL EGR 시스템을 적용하였고 CO와 THC, PM 배출가스를 줄이기 위해 DOC와 DPF를 사용하였다. EGR 시스템을 적용하기 위해 각 조건에 대한 기본 실험을 실시하여 EGR map을 작성하였다. 작성된 map을 NRTC 모드에서 시험하여 map의 적용성을 검증하고 tier 4 interim 배기규제 만족여부를 파악하였다.

• 청정기술
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• 제22권4호
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• pp.211-224
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• 2016

가솔린 자동차의 내연기관 배기가스 처리를 위한 촉매로 삼원촉매가 널리 사용되고 있다. 반면 디젤 자동차의 배출 오염 물질 처리를 위해서는 다양한 기술들이 연구개발되고 있다. 디젤 자동차의 특징인 희박연소 조건에서 발생하는 질소산화물의 저감과 제거를 위해 티타니아에 담지된 바나듐 촉매가 상용화되어 있다. 바나듐 촉매를 이용한 질소산화물 저감기술은 암모니아를 환원제로 이용함으로써 대형 디젤 차량에 효과적으로 적용할 수 있다. 최근 활발하게 연구개발이 이루어지고 있는 구리가 이온 교환된 제올라이트 촉매는 초고연비 자동차 개발의 필수 기술로 인식되고 있다. 본 총설에서는 디젤 엔진의 배기가스 중 질소산화물을 효과적으로 제거하기 위한 후처리 기술 중 하나인 암모니아를 이용한 선택적 촉매 환원 반응의 촉매로 사용되는 구리가 이온 교환된 제올라이트 촉매와 관련한 최근 연구개발 동향을 소개하고자 한다.

• 동력기계공학회지
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• 제22권1호
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• pp.56-63
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• 2018

After the recent fabrication of diesel vehicle exhaust gas by Volkswagen, nitrogen oxides ($NO_x$) and particulate matter (PM) are drawing attention as representative pollutants included in exhaust gas. When gasoline and diesel fuels are combusted through direct injection into a combustion chamber at high pressure, PM emission is actually increased. To find a solution to this problem, a basic study was conducted to derive an optimized variable for combustion of compressed natural gas (CNG) by applying CNG, acknowledged as a clean fuel, to direct injection system. The essence of this study is in the introduction of a radical ignition technology for compressed natural gas (RI-CNG) in a sub-chamber type engine. The direct injection system was applied to a sub-chamber to remove residual gas from previous combustion cycle. In addition, optimal mixer distribution was achieved by precisely setting ignition timing based on fuel injection timing and excess air ratio.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2007년도 추계학술대회 논문집
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• pp.115-116
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• 2007

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2009년도 추계학술대회 논문집
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• pp.314-315
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• 2009

• 오토저널
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• 제14권6호
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• pp.67-73
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• 1992

This paper describes Hyundai's research and development work on a flexible fuel vehicle (FFV). The work on FFV has been conducted to evaluate its potential as an alternative to the conventional gasoline vehicle. Hyundai FFV described here can be operated on M85, gasoline, or any of their combinations, in which the methanol concentration is measured by an electrostatic type fuel sensor. For that operation, a special FFV ECU(Eletronic Control Unit) has been developed and incorporated in the FFV. The characteristics affecting FFV operation, such as FFV ECU control strategy and injector flow rate, have been investigated and optimized through the experiment. And various development tests have been performed in view of engine performance, durability, cold startability, and exhaust emissions reduction. The exhaust gas aftertreatment system consisting of manifold type catalyst and secondary air injection system shows good emission reduction performance including formaldehyde, and finally, the possibility of the FFVs as the low emission vehicles is evaluated by presenting NMOG(Non-Methane Organic Gases) levels with respect to M0 and M85. With these results, it is concluded that FFV can be a candidate for the low emission vehicles, but more works on its durability improvement is required.

• 한국정밀공학회지
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• 제28권2호
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• pp.185-192
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• 2011

This study deals with a basic proposal to prove the safety for the exhausted fittings of the hydrogen fuel cell vehicle. First, this study was approached to numerical analysis solving to close the exact boundary condition (Axial, Bending, Lateral) and the second, this study produced the Lateral movement equipment for the vibration. For the numerical analysis, This study was considered with the exact solution of Lateral movement and the resonance effect for durability sample according to fitting positions. The second, This study was made for special equipment for displacement/gas leak and the frequency because the domestic samples were comparing with foreign fitting and foreign fitting for the hydrogen fuel cell vehicle. The result of this study was satisfied with domestic fittings for the basic reference but it need more test because of other situation for hydrogen fuel cell vehicle.

• 한국자동차공학회논문집
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• 제22권5호
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• pp.73-83
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• 2014

CFD(computational fluid dynamics) model is developed to simulate direct injection of ammonia gas phase from ammonia transporting materials into the SCR catalyst in the exhaust pipe of the engine with solid SCR. Configurations of one-hole and four-hole nozzle, circumferential type, porous tube type, and the effect of mixer configurations which commonly used in liquid injection of AdBlue are considered for complex geometries. Mal-distribution index related to concentration of ammonia gas, flow uniformity index related to velocity distribution, and pressure drop related to flow resistance are compared for different configurations of complex geometries at the front section of SCR catalyst. These results are used to design the injection system of ammonia gas phase for solid SCR of target vehicle.