• 한국자동차공학회논문집
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• 제11권2호
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• pp.75-82
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• 2003

DME is a good alternative fuel to reduce the smoke remarkably when used in a diesel engine, while problems concerned with low lubricity and high compressibility exist. In the present study, single cylinder DI diesel engine was operated with neat DME and DME blended fuels which are DME-diesel blended fuel and DME-propane blended fuel. The results showed that the power of the neat DME and DME blended fuels was the same as that of pure diesel oil, and the specific energy consumption slightly increased. In addition, smoke emission was considerably reduced with the increase of DME content up to zero level, but NOx emission was slightly increased.

• 한국항해항만학회지
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• 제46권4호
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• pp.297-302
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• 2022

탄산칼슘과 염산 수용액에 폴리프로필렌 섬유를 침지시켜 표면에 염화칼슘 결정을 생성시킴으로써 발열 흡착포를 제작하였다. 발열 흡착포를 유출 기름으로 인해 유막이 형성된 해수면에 적용하면 염화칼슘 결정이 주변의 수분을 흡수하여 이온화되면서 용해열을 방출한다. 염화칼슘의 용해열을 유동점 이하의 저온에서 응고된 저유황 중질유를 액화시켜 흡유 가능한 상태로 전환시킨다. 발열 흡착포의 제작을 위해 폴리프로필렌 표면에 염화칼슘 결정을 생성시키기 위한 탄산칼슘과 염산의 최적 몰농도는 각각 0.25 M과 0.5 M이다. 저유황 중질유 발열 흡착포의 흡유능은 해수 온도에 따라 다르지만, 우리나라 인근 해역의 동절기 평균 수온인 10℃에서 4.5-7.08 g/g으로 매우 우수하였다. 염화칼슘 발열 흡착포를 사용하면 동절기 선박사고로 인하여 해양에 유출된 저유황 중질유를 효과적으로 흡유하여 제거할 수 있다.

• 한국추진공학회지
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• 제13권3호
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• pp.58-63
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• 2009

세계적으로 강화되는 오염물질 배출규제와 유가의 급등은 미래 수송수단의 변화를 가져올 것으로 예상된다. 새로운 대체에너지가 나타나기 까지는 화석연료를 대체할 에너지원으로 수소가 가장 유력하다. 가까운 미래의 항공기는 수소 가스터빈엔진이나 연료전지와 같은 동력장치를 사용할 것으로 과학자들은 예측하고 있다. 향후 연료전지 동력 항공기가 실현되기 위해서는 동력밀도가 높은 연료전지, 고압의 기체 또는 액체상태의 수소연료저장 장치, 그리고 경량의 고효율 전기모터가 개발되어야 한다.

• Korean Chemical Engineering Research
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• 제61권4호
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• pp.591-597
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• 2023

Pakistan depends heavily on imports for its fuel requirements. In this experiment, catalytic pyrolysis of a blend of feedstock's consisting of date seed, wheat straw, and corn cob was conducted in a fixed bed reactor to produce oil that can be used as an alternative fuel. The main focus was to emphasize the outcome of important variables on the produced oil. The effects of operating conditions on the yield of bio-oil were studied by changing temperature (350-500 ℃), heating rate (10, 15, 20 ℃/min), and particle size (1, 2, 3 mm). Moreover, ZnO was used as a catalyst in the process. First, the thermal degradation of the feedstock was investigated by TGA and DTG analysis at 10 ℃/min of different particle sizes of 1, 2, and 3mm from a temperature range of 0 to 1000 ℃. The optimum temperature was found to be 450 ℃ for maximum degradation, and the oil yield was indicated to be around 37%. It was deduced from the experiment that the maximum production of bio-oil was 32.21% at a temperature of 450 ℃, a particle size of 1mm, and a heating rate of 15 ℃/min. When using the catalyst under the same operating conditions, the bio-oil production increased to 41.05%. The heating value of the produced oil was 22 MJ/kg compared to low-quality biodiesel oil, which could be used as a fuel.

• 한국자동차공학회논문집
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• 제16권5호
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• pp.147-156
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• 2008

As the management of fuel efficiency becomes globally reinforced in attempts to find an environment-friendly vehicle that will operate against global warming, the interest in and the demand for the type of vehicle with a high-efficiency diesel engine using light oil. However, it also emits a greater amount of PM (particulate matter) and NOx than emissions from vehicles using other types of fuels. Therefore, the DME (Dimethyl Ether), an oxygen containing fuel draws attention as an alternative fuel for light oil that can be used for diesel engines since it generates very little smoke. But to develop and compare performance of an electric controlled common-rail DME engine, engine tests requires optimized injection conditions at required engine RPM and engine torque. These injection conditions cannot be set freely and the data configuration through the experimentally repeated application requires much time as well as a significant amount of errors and effort. The object of this study is to configure the basic injection map using the results of the DME engine experiments performed so far. For this, in this study, the functionalization of the required equations were performed along with the basic review of the factors that had influence on the data map. Through this, the information on the injection pressure, injection amount, injection duration, injection timing, etc. under certain operation condition could be obtained.

• 수산해양기술연구
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• 제53권1호
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• pp.89-97
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• 2017

Butanol has an ability to improve the ignition quality due to its lower latent heat of vaporization; it has an advantage to reduce a volume of a fuel tank because its energy density is higher than that of ethanol. Also, butanol-diesel oil blending quality is good because butanol has an effect to prevent the phase-separation between two fuels. Even if the blended oil contains water, it can reduce the corrosion of the fuel line. Thus, it is possible to use butanol-diesel oil blended fuel in diesel engine without modification, and it may reduce the environment pollution due to NOx and particulate and the consumption of diesel oil. Therefore, some studies are being advanced whether butanol is adequate as an alternative fuel for diesel engines, and the results of the combustion and exhaust gas emission characteristics are being presented. Though the injection and spray characteristics of butanol are more important in diesel combustion, the has not yet dealt with the matter. In this study, the influence in which differences of physical properties between butanol and diesel oil may affect the injection and spray characteristics such as injection rate, penetration, spray cone angle, spray velocity and process of spray development were examined by using CRDI system, injection rate measuring device and spray visualization system. The results exhibited that the injection and macroscopic spray characteristics of two fuels were nearly the same.

• 한국대기환경학회지
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• 제24권2호
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• pp.189-195
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• 2008

We developed emission factors for alternative fuels used in cement industries in Korea and also estimated reduction in emissions of greenhouse gas (GHG) by the use of alternative fuels. Emission factors for GHG of waste tire, waste plastic, waste oil and RDF were estimated to be about 89, 78, 77 and 95 ton $CO_2$/TJ respectively. When compared with previous studies, most of the results showed similar trends. The calorific value estimation and elemental analysis for energy source were implemented in order to estimate the exact emission factors and the reduction of GHG emissions using alternative fuel. In the case of 'A' company, $CO_2$ emission from alternative fuels was about 4% lower than that of bituminous coal only. Also in case of company 'B', $CO_2$ emission from alternative fuels was about 1.4% lower than that of only bituminous coal. In Germany and Japan, alternative fuel is not regarded to be fuel consumption in cement industry. When applying this rule, the emission reductions were about 4.3% for company 'A' and 6.3% for company 'B'. The results of this study may be considered as a useful information for developing strategies in reducing GHG emissions.

• 한국자동차공학회논문집
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• 제3권6호
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• pp.112-122
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• 1995

As an alternative fuel producing less exhaust emissions, natural gas is of interest for use both in SI and CI engines. The potential of natural gas fuelled dual-fuel engine is considered high enough. However, much effort has to be made so that gaseous fuel is used efficiently with simultaneous minimum use of pilot oil. Hence, a simplified three-dimensional model, using a finite volume method in cylindrical coordinates, has been developed to facilitate an understanding of the dual-fuel combustion phenomena and to predict the complex interactions between the pilot distillate and natural gas. The computer model was calibrated by comparing it with the experimental results obtained from diesel engine like combustion bomb tests. In the pre-mixed natural gas combustion, the fuel burning was highly reliant on the injection condition and subsequent burning nature of the pilot distillate.

• 한국자동차공학회논문집
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• 제25권3호
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• pp.380-388
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• 2017

Wood pyrolysis oil(WPO) has been regarded as an alternative fuel for diesel engines. However, WPO is not feasible for use directly in diesel engines due to its poor fuel quality such as low energy density, high acidity, high viscosity and low cetane number. The most widely used approach to improve WPO fuel quality is to blend WPO with other hydrocarbon fuels that have a higher cetane number. However, WPO and fossil fuels are not usually blended because of their different polarity. Also, clogging and polymerization problems in the fuel supply system can occur when the engine is operated with WPO. Polymerization can be prevented by diluting WPO with other alcohol fuels. However, WPO-alcohol blended fuel does not produce self-ignition. Therefore, additional cetane enhancement to the blended fuel is required to enhance auto-ignitability. In this study, WPO was blended with n-butanol and two cetane enhancements(PEG 400 and 2-EHN) for application to a diesel generator. Experimental results showed that the WPO-butanol blended fuel achieved a very stable engine operation under maximum WPO content of 20 wt%.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.277-279
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• 2005

The imbalance of energy demand and supply caused by rapid industrialization around the world and the associated environmental issues require and alternative energy source with possible renewable fuels. Political instability and depletion of cruel oils are other factors that cause fluctuation of oil price. Securing a new alternative energy source for the next century became an urgent issue that our nation is confronting with. As a matter of fact, the fuel cell technology can be widely used as next generation energy regardless of regions and climate. Specially, the ability of expansion and quick installation enable one to apply it for distributed power, where the technology is already gaining remarkable attentions for the application. Particularly, leading industrialized nations are focusing on the PEM fuel dell with anticipation that this technology will find their place of applications in the vehicles and homes. In this study, demonstrate the multi physics modeling of a proton exchange membrane(PEM) fuel cell with interdigitated flow field design. The model uses current balances, mass balance(Maxwell-Stefan diffusion for reactant, water and nitrogen gas) and momentum balance(gas flow) to simulate the PEM fuel cell behavior.