• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.3
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• pp.335-342
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• 2012

Nowadays, automobile manufacturers are focusing on the reduction of exhaust-gas emissions because of the harmful effects on humans and the environment, such as global warming by greenhouse gases. Gasoline direct injection (GDI) combustion is a promising technology that can improve fuel economy significantly compared to conventional port fuel injection (PFI) gasoline engines. In the present study, ultra-lean combustion with an excess air ratio of over 2.0 is realized with a spray-guided-type GDI combustion system, so that the fuel consumption is improved by about 13%. The level of exhaust-gas emissions and the operation performance with the multiple injection strategy and exhaust-gas recirculation (EGR) are examined in comparison with the emission regulations and from the point of view of commercialization.

• Journal of Institute of Convergence Technology
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• v.3 no.2
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• pp.57-60
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• 2013

The purpose of this study is to analysis of how to calculate fuel efficiency in major development countries (U.S. and Europe) and energy consumption formular derivation of domestic CNG fuel and prove by vehicle test. The formula of fuel consumption is different in mpg(mile per gallon), l/100km, and km/l each countries. CNG fuel has a significant impact on fuel density, composition, and Hydro-Carbon ratio. So, this study how to measurement and calculation procedures of CNG gaseous fueled vehicle energy consumption rate.

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.5
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• pp.603-608
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• 2012

Recently we have a growing interest in environmental pollution and alternative energy. Diesel engine is generally used to produce the power on shore and sea. However, the combustion characteristics and exhaust emissions of the engine are changed on account of the wear of fuel system and the altered ambient condition of the combustion chamber by the increment of the engine operation hour. Therefore the combustion characteristics and exhaust emissions on the fuel injection timing were experimentally investigated to find out the optimum fuel injection timing in case of the about 20 years used diesel engine using biodiesel blend oil. The original fuel injection timing of the engine is BTDC $22^{\circ}$ CA. However, it is found that the optimum fuel injection as a result of analyzing the specific oil consumption and exhaust emissions of 20 years used the engine is BTDC $26^{\circ}$ CA.

• Journal of Energy Engineering
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• v.6 no.2
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• pp.212-219
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• 1997

The objective of this study is to investigate the effects light diesel-water emulsified fuel on performance and exhaust emissions of the compression ignition engine. The experimental results of light diesel-water emulsified fuel operation with new type ultrasonic emulsification apparatus as compared with light diesel operation are very positive; maximum 28% reduction of SFC (in the case of 30% of water content), maximum 60% reduction of smoke (in the case of 30% of water content), maximum 79% reduction of CO emission (in the case of 30% of water content). However, comparing light diesel-water emulsified fuel and light diesel in the same engine under the same operating conditions, power and torque were lower in the case of emulsified fuel. In view of the results for the above mentioned, the mixing of water into light diesel in the form of emulsification proved to be the best means for reduction of specific fuel consumption and exhaust emissions of C.I. engines.

• Fire Science and Engineering
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• v.33 no.5
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• pp.1-6
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• 2019

The recent development of biofuel production technology facilitates the widespread use of bioethanol and biodiesel by mixing them with fossil fuels. However, the use of these new blended fuels in combustion could result in severe safety problems, such as fire and explosion. In this study, numerical simulation was performed on the well-stirred reactor (WSR) to simulate the autoignition temperature (AIT) in homogeneous combustion and clarify the effect of ethanol addition on the AIT, the most important property for assessing the potential for fire and explosion. Response surface methodology (RSM) was introduced as a design of experiment (DOE), enabling the AIT to be predicted and optimized systematically with respect to three independent variables: ethanol mole fraction, equivalence ratio, and pressure. The results show that the autoignition temperature primarily depends on the ethanol mole fraction and pressure, while the effects of the equivalence ratio are independent of the AIT. RSM accurately predicted the experimental AIT, indicating that this method can be used to effectively predict the key properties involved in fires and explosions.

• Korea Petroleum Association Journal
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• no.9 s.31
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• pp.62-65
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• 1983

세계 LNG 생산량은 최근 2년간 큰 변동이 없다 82년의 경우 전년비 1.6%감소했으나 이는 81년도 생산증가율보다는 다소 낮은 수치이다. 가채확인 매장량은 지난 해 3.6%증가했으며, 지난 5년간 누계로는 32.4%나 늘어났다. 그러나 이들 통계이면에는 가스소비의 지역적 격차와 구조적 변화가 크게 나타나고 있다. 가스는 정체된 세계시장에서 연료로서의 위치를 확고히 하고 있으나. 타연료와의 경쟁력이 약해 시장확대는 이루어지지 않고 있다.

• Electric Engineers Magazine
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• v.182 no.10
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• pp.39-43
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• 1997

에너지수요의 확대 중장기적인 자원제약의 현재화 등에 따라 에너지의 안전공급확보 필요성이 점점 높아지고 있는 한편 에너지 소비의 증대에 의한 지구환경의 오염, 온난화 등이 세계적인 문제로 대두되고 있다. 이에 따라 새로운 에너지절약 및 신에너지 기술개발의 기운이 고조되어가고 있으며 특히 연료전지는 고효율이 고 배기가스가 깨끗한 환경적합성에 우수한 차세대 열병합발전시스템으로서 실용화가 기대되고 있다.

• TTA Journal
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• s.54
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• pp.99-113
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• 1997

전 세계적으로 차량의 숫자는 급격하게 증가하는데 비해 도로 증가율이 이에 미치지 못해 교통 체증으로 인한 경제적, 인적 손실이 국가 산업 경쟁력을 위협하는 수준이 되었다. 이를 극복하기 위해 기존의 도로교통 체계에 첨단 정보통신 및 교통, 제어 체계를 도입하여 교통혼잡 및 환경오염, 연료소비의 감소와 안전운행 확보를 위한 ITS 연구 개발이 활발하게 진행중에 있다.

• Journal of Korean Society of Forest Science
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• v.94 no.3 s.160
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• pp.135-145
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• 2005

The purpose of this study is to reveal the component characteristics and the channels of distribution for forest products as a fuel that were consumed in Kyeongseong city (Seoul) in 1929, in the middle of the colonial period. The summary of the results are as follows; (1) though the average consumption of forest products consumed as a fuel per household in Kyeongseong city was slightly less than one-third as much forest products as fuel consumed in other counties of Kyeongki province, but due to the high heat capacity, the amount of fuelwood and charcoal consumption was much higher than leaf and grass consumption; (2) the largest supply areas of forest products for fuel were the riverside of Kangwon province and Kyeonggi province in which the waterways were available. They supplied 42.6% of total consumption, and the other supply areas were the northern part of Kyeonggi province, etc. (29.5%) where railroads were handy, and the suburbs of Kyeongseong City (27.9%) by roads; (3) the transportation areas using the Han River were divided into two parts of Ttook island (43.0%) and former Yongsan and Mapo (45.6%), but the volume of transportation by railroad was centralized in Kyeongseong Station, which accounted for 72.2% of total volume of transportation by rail; (4) the most of the forest products consumed for fuel in Kyeongseoung city were sold in temporary fuelwood markets, rather than permanent and regular markets.

• Journal of the korean Society of Automotive Engineers
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• v.7 no.1
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• pp.18-23
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• 1985

내연기관은 자동차용 기관에 의하여 일반대중과 접촉하게 되었으며, 특히 20세기 중반에 이르러 자동차라는 기계가 일반가정에서 사용되는 가구로 탈피하는 과정에서 그 중요장치의 하나인 자동차용 기관도 전문가가 취급하는 기계로부터 일반인이 취급하는 가구로의 탈피를 요구함에 따라 크게 발전해 온 것이 사실이다. 종래, 내연기관의 설계에 있어서 그 출력과 연료소비를 가장 중요한 성능평가의 요소로 삼아왔지만, 가구로서의 자동차의 최적화를 위해서는 더욱 중요한 많은 성능평가의 요소가 있다는 것을 인식할 필요가 있다고 생각한다. 실은 최적화에 필요한 많은 요소의 균형을 어떻게 할 것인가 하는 것이 자동차용 기관의 설계에 있어서 가장 중요한 일이라 생각되며, 자동차용 기관을 계획할 때의 목표는 다음과 같은 3가지로 생각된다. (1) 고성능일 것 (2) 우수한 기능을 가질 것 (3) 공해가 없을 것 (1)의 고성능을 추구하는데 있어서는 비출력, 연료소비율 및 양호한 응답성이 중요한 요소로 된다. 이중 응답성의 문제는 연료공급기구나 조속기 등의 기능적인 요소와 깊은 관련이 있다. 그리고 내구성, 신뢰성, 정비점검의 무용성이라는 것이 (2)의 우수한 기능을 보장하기 위한 가장 중요한 배경으로 된다. 또한 진동이나 소음이 없고 정숙할 것이 (3)의 무공해성의 목표와도 관 련되는 중요한 요소이다. 배출가스의 무공해화가 자동차에 의한 공해방지의 입장으로부터 중요한 요소가 되는 것은 주지의 사실이다. 그리고 이 배출가스의 청정화의 문제는 성능향상을 위한 비출력증대의 방향에 대한 방해가 되는 문제이다. 이상 기술한 바와 같은 설계단계에 있어서의 계획목표를 3가지로 설정하고, 이 3가지 목표에 관련되는 요소의 균형을 어떻게 위해야 할 것인가 하는 점에 초점을 맞추어 되도록 쉽게 기술하고자 하였으나, 미비한 점이 많았을 것으로 생각하여, 다만 이 분야에 종사하는 기술자 여러분에게 약간의 도움이라도 되었으면 하는 것이 소망이다.