• Journal of Biosystems Engineering
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• 제32권5호
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• pp.279-283
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• 2007

In this study, the potential possibility of oxygenates on di-ether group (DBE, dibutyl ether) was investigated as an additives for an agricultural direct injection diesel engine. It tested to estimate change of engine performance and exhaust emission characteristics for the commercial diesel fuel and oxygenates additives blending fuel which has four kinds of mixed ratio. The smoke emission of blending fuel (diesel fuel 80 vol-% + DBE 20 vol-%) was reduced in comparison with diesel fuel, that is, it was reduced approximately 26% at 2500 rpm, full load. And, power, torque and brake specific energy consumption didn't have large differences. But, NOx emission of blended fuel was increased compared with commercial diesel fuel.

• 동력기계공학회지
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• 제6권1호
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• pp.27-35
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• 2002

In this paper, the effect of oxygen component in fuel on the exhaust emissions has been investigated for direct injection diesel engine. It is tested to estimate change of engine performance and exhaust emission characteristics for the commercial diesel fuel and oxygenate blended fuel which has four kinds of mixed ratio. And, the effects of exhaust gas recirculation(EGR) on the characteristics of NOx emission and brake specific fuel consumption rate have been investigated. Dimethyl carbonate(DMC) contains oxygen component 53.3% in itself, and it is a kind of effective oxygenated fuel of carbonate group that the smoke emission of DMC is reduced remarkably in comparison with commercial diesel fuel, that is, it can supply oxygen component sufficiently at higher loads and speeds in diesel engine. It was found that simultaneous reduction of smoke and NOx was achieved with oxygenated fuel and EGR method.

• 한국자동차공학회논문집
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• 제11권1호
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• pp.79-86
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• 2003

In this paper, the effect of oxygen component in fuel on the exhaust emissions has been investigated fur direct injection diesel engine. It was tested to estimate change of engine performance and exhaust emission characteristics for the commercial diesel fuel and oxygenated blended fuel which has seven kinds of mixed ratio. And, the effects of exhaust gas recirculation(EGR) on the characteristics of NOx emission have been investigated. Ethylene glycol mono-n-butyl ether(EGBE) contains oxygen component 27% in itself, and it is a kind of effective oxygenated fuel of mono-ether group that the smoke emission and unburned hydrocarbons of EGBE is reduced remarkably compared with commercial diesel fuel, that is, it can supply oxygen component sufficiently at higher loads and speeds in diesel engine. It was found that simultaneous reduction of smoke and NOx was achieved with oxygenated fuel and cooled EGR method.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년 영문 학술대회
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• pp.579-582
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• 2008

PEM Fuel cell system was designed and constructed to use as a power source of unmanned aerial vehicles(UAV) in the present study. Sodium borohydride was selected as a hydrogen source and was decomposed by catalytic hydrolysis reaction. Fuel cell system consists of a fuel cell stack, a hydrogen generation system(HGS), and power management system(PMS). HGS was composed of a catalytic reactor, micropump, fuel cartridge, and separator. Hybrid power system between lithium-polymer battery and fuel cell was developed. The fuel cell system was integrated and packaged into a blended wing-body UAV. Energy density of the total system was 1,000 $W{\cdot}hr/kg$ and high endurance more than 5 hours was accomplished in the ground tests.

• 대한기계학회논문집B
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• 제35권12호
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• pp.1359-1365
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• 2011

본 연구의 목적은 디젤-에탄올 혼합연료로 운전되는 디젤엔진에서 에탄올 혼합비율이 나노 크기 입자 배출 특성에 미치는 영향을 분석하는 것이다. 엔진의 연소 및 배기 배출물 특성은 배기량 373cc 의 단기통 디젤엔진과 배기 배출물 측정 장치, SMPS 를 이용하여 실험하였다. 그을음(soot) 배출은 착화지연 기간이 길어짐에 따라 증가하였다. 에탄올 혼합비율이 증가함에 따라 나노 입자의 총 개수 및 질량은 대체로 감소하는 경향을 나타냈다. 그러나 에탄올이 30% 혼합되었을 때 그을음(soot) 입자의 응결로 인해 큰 입자의 수 분포가 증가하였으며, 질량 또한 크게 증가하였다.

• Korean Chemical Engineering Research
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• 제50권3호
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• pp.464-470
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• 2012

DME 및 LPG 혼합연료에 대한 혼합도 분석 실험을 수행하였다. DME 20 wt%와 LPG(주성분 프로판) 80 wt%를 탱크에 순차적으로 주입하여 시간 경과에 따라 탱크의 각 측정부에서의 농도를 측정하였다. 먼저 DME가 주입되고 그 후에 프로판이 주입되면서 DME의 일부는 혼합이 되나 일부는 혼합이 되지 않고 밀도차에 의해서 탱크 하부로 가라앉게 되는 층상화 현상이 발생하였다. 1일 경과 시 약 0.2~0.3 wt%의 증가비율로 두 연료가 혼합되어 완전히 균일하게 되기까지 약 500시간 이상이 소요되었다. 또한 재순환 펌프를 가동하여 탱크 내 연료를 순환 시킨 후 혼합 연료의 성분을 측정한 실험에서는 DME와 프로판이 균일하게 혼합됨을 확인하였다.

• Journal of Advanced Marine Engineering and Technology
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• 제37권1호
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• pp.53-58
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• 2013

비에스테르화 대두유의 활용 가능성을 평가하기 위해 현재 대부분의 디젤 자동차에 채택되어 있는 전자 제어 분사식 과급디젤기관에 경유, 에스테르화 바이오 디젤유 5% 및 비에스테르화 대두유 5% 혼합유를 사용하여 성능 실험을 실시하였다. 그 결과, 에스테르화 바이오 디젤유 5%와 비에스테르화 대두유 5%의 연소성능이 대부분 비슷하지만 NOx는 비에스테르화한 것이 더 적게 배출되었고 이는 Fuel NO에 의한 것을 밝혔다.

• Carbon letters
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• 제25권
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• pp.78-83
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• 2018

Pyrolyzed fuel oil (PFO) and coal tar was blended in the feedstock to produce pitch via thermal reaction. The blended feedstock and produced pitch were characterized to investigate the effect of the blending ratio. In the feedstock analysis, coal tar exhibited a distinct distribution in its boiling point related to the number of aromatic rings and showed higher Conradson carbon residue and aromaticity values of 26.6% and 0.67%, respectively, compared with PFO. The pitch yield changed with the blending ratio, while the softening point of the produced pitch was determined by the PFO ratio in the blends. On the other hand, the carbon yield increased with increasing coal tar ratio in the blends. This phenomenon indicated that the formation of aliphatic bridges in PFO may occur during the thermal reaction, resulting in an increased softening point. In addition, it was confirmed that the molecular weight distribution of the produced pitch was associated with the predominant feedstock in the blend.

• 동력기계공학회지
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• 제17권2호
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• pp.29-37
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• 2013

Compared to gasoline engines, diesel engines with a relatively simple ignition system are more advantageous in the application of biodeisel fuel to engine. Then in this study the comparative analysis on the spray characteristics and combustion emissions characteristic between the biodiesel(soybean oil) and diesel, the fuel for commercial diesel engine, was performed with common rail injection system. Injection pressure and ratio of biodiesel blended fuel were selected as main experimental variables. Consequently, it can be found that there is no significant difference in the macro characteristics of the spray behavior(spray penetration and spray angle) in response to change in the blend ratio of soybean oil and diesel at a fixed injection pressure, in particular, soot creation in combustion emissions in the region of low pressure was greatly affected by the blend ratio of soybean oil, however, the creation in the region of high pressure was almost unaffected by the blend ratio because of promoted atomization.

• 에너지공학
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• 제19권3호
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• pp.171-176
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• 2010

천연가스-수소 혼합가스를 엔진 연료로 사용하는 방법은 배기가스 저감뿐만 아니라 다가올 수소에너지 시대를 대비하여 수소 인프라를 구축하는 데도 의의가 있다. 또한 수소 혼합 천연가스 연료 엔진은 천연가스 엔진 보다 더 높은 열효율 확보할 수 있어 에너지의 효율적 사용에 있어서도 매우 우수한 연료이다. 본 연구에서는 시내버스가 가장 많이 운전되는 조건인 아이들 조건을 대상으로 수소 혼합 천연가스 연료가 연료소모량과 배기가스 저감에 미치는 영향을 파악하였다. 실험 결과 수소 혼합 천연가스 연료는 천연가스에 비해 아이들 조건에서 연료소비율이 20%이상 저감되었으며 유해 배출가스인 THC, NOx를 근원적으로 저감시킴을 확인할 수 있었다.