• 한국가스학회지
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• 제2권2호
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• pp.12-17
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• 1998

급속한 도시가스 보급률의 증가로 인해 국내 도시가스시설에서는 많은 사고가 일어났었다. 이러한 도시가스 사고에 대한 예방 대책으로 여러 관련기관에서는 도시가스의 물성치등 안전 관련 자료들과 도시가스시설에 대한 정보들을 부분적으로 구축$\cdot$관리하고 있다. 하지만 각 기관들이 구축한 정보들을 공유하고 있지 않기 때문에 정보들을 중복되게 구축$\cdot$관리하고 있어 이에 대한 효율성이 결여되어 있다. 따라서 정보 관리와 공유를 효과적으로 할 수 있으며, 정보들을 이용하여 정량적 위험성 평가 및 방재 계획을 지원할 수 있는 지리정보시스템에 관한 연구를 하였다.

• Journal of Advanced Marine Engineering and Technology
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• 제35권5호
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• pp.566-575
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• 2011

LPG 연료공급방식은 배출가스를 저감시킬 수 있는 유용한 시스템으로 연구가 지속적으로 진행되고 있다. LPG는 경유와 휘발유보다 높은 증기압과 낮은 점도와 표면장력을 유지하므로 고무류와 화학 반응에 따른 연료펌프의 기계적인 손상으로 내구성이 저하되고 있는 실정이다. 본 연구에서는 이러한 문제점을 해결하기 위해 LPLi 시스템에서 유지보수의 편리함과 가격경쟁을 위해 개발된 외장형 펌프를 사용하여 LPG 연료의 조성 및 온도에 따른 특성을 평가하고자 실험을 하였다. 그 결과로서, 내장형 펌프와 외장형 펌프의 성능차이는 거의 없으며 프로판 함유율이 높고, 연료온도가 높아짐에 따라 유량은 많아지나 펌프효율은 거의 차이가 없었다. 또한 LPG 자동차 연료공급장치의 특성상 연료조성 및 온도변화에 따른 차압도 거의 일정하게 나타내었다.

• 한국수소및신에너지학회논문집
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• 제22권2호
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• pp.191-198
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• 2011

According to the propagation of fuel cell system, the importance of that system efficiency is being magnified. Thus, the efficiency improvement of reformer which is the important factor of fuel cell system will be required. This study has been experimentally performed to evaluated the performance of plate type STR reactor. At first, we changed fuel flow rate (2, 3 and 4 l/min) in burner, and then we measured a proportion of hydrogen in produced gas through the STR reactor by G.C for evaluating the performance of plate type STR reactor in various fuel supply conditions. And we changed S/C ratio (2 and 4) and measured a proportion of hydrogen in produced gas through the STR reactor. As a results, condition at fuel flow rate 2 and 3 l/min could not be supplied amount of heat for STR sufficiently. Condition at fuel flow rate 4 l/min could supplied a heat excessively. And condition at S/C ratio 2, reaction occurred insufficiency. But condition at S/C ratio 4 was excess. From above, we found the optimum conditions that were fuel rate 3.5 l/min and S/C ratio 3.

• 항공우주기술
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• 제12권1호
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• pp.200-206
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• 2013

액체로켓엔진에서 추진제 밀도와 공급 압력 변화에 대한 성능 민감도를 분석하였다. 해석 프로그램은 터보펌프-가스발생기 연계시험 결과와 비교하여 1% 오차를 가지는 것으로 확인되었다. 연료 공급압력이 증가하면 혼합비 감소로 인해 엔진 연소압이 감소하였고 연료의 밀도가 증가하면 혼합비 감소에도 불구하고 추진제 유량이 증가하므로 엔진 연소압이 증가하는 것으로 예측되었다. 또한 산화제의 밀도가 증가되거나 공급압력이 증가하면 엔진의 연소압이 증가할 것으로 분석되었다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2013년도 제46회 KOSCO SYMPOSIUM 초록집
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• pp.83-85
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• 2013

With an increase in the use of low rank coals in power plants, various operational issues were raised in the fuel storage and supply, combustion, boiler and flue gas treatment systems. In the fuel storage and supply system, the main issue is the self-heating propensity of low rank coals leading to spontaneous combustion in yard storage, transport and pulverization. This study evaluated the reactivity of various sub-bituminous and bituminous coals with oxygen at low temperatures by analyzing the temperature increase characteristics of coals under a constant flow rate of oxygen supply. The results were quantified to a self-heating index and the relation with the fuel properties were evaluated.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.561-564
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• 2007

FCEV uses electric energy which generated from the reaction between Hydrogen and Oxygen in fuel cell stack as driving force. As fossil fuels are exhausted, fuel cell is regarded as a potent substitute for next generation energy source, and thus, most of car-makers make every efforts to develop fuel cell electric vehicle (FCEV). In addition, fuel cell is also beneficial in aspect of environment, because only clean water is produced during chemical reaction process instead of harmful exhausted gas. Generally, Hydrogen is supplied from high-pressured fuel tank, and air blower (or compressor) supply Oxygen by pressurizing ambient air. Air blower which is driven by high speed motor consumes about $7{\sim}8$ % of energy generated from fuel cell stack. Therefore, the efficiency of an air blower is directly linked with the performance of FCEV. This study will present the development process of an air blower and its consisting parts respectively.

• 한국수소및신에너지학회논문집
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• 제31권5호
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• pp.405-410
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• 2020

In this literature, we are introduce a basic design of multi energy hub based on natural gas governor station. Multi energy hub consists of turbo expender generator, phosphoric acid fuel cell, pressure swing adsorption, H₂ charging station, utilities and etc. We design a hybrid energy hub system that provides energy using these complex energies, and calculates the amount of electricity that can be produced and the amount of hydrogen charged through the process analysis. TEG and phosphoric acid fuel cell produce 2,290 to 2,380 kW and can supply electricity to 500 houses. In addition, By-product H₂ gas is refined to H₂ vehicle fuel. This will help maximize the balance of energy demand and supply and improve national energy efficiency by integrating unused decompression energy power generation technology and various power generation/heat source technologies.

• 한국수소및신에너지학회논문집
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• 제27권5호
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• pp.485-493
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• 2016

Recently submarine and unmanned underwater vehicle (UUV) are equipped with a fuel cell system as an air independent propulsion system. Methanol fuel processor can efficiently supply the hydrogen to the fuel cell system to improve the ability to dive. This study investigated the optimal conditions of the methanol fuel processor that may be used in the closed environment. For this purpose, the numerical model based on Gibbs minimization equation was established for steam reformer and three exhaust gas burners. After simulating the characteristics of steam reformer according to the steam-to-carbon ratio (SCR) and the pressure change, the SCR condition was able to narrow down to 1.1 to 1.5. Considering water consumption and the amount of heat recovered from three burners, the optimum condition of the SCR can be determined to be 1.5. Nevertheless, the additional heat supply is required to satisfy the heat balance of the methanol fuel processor in the SCR=1.5. In other to obtain additional amount of heat, the combustion of methanol is better than the increased of SCR in terms of system design.

• 한국가스학회지
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• 제13권4호
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• pp.1-7
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• 2009

최근 연료경제성 및 강화되는 배출가스 규제를 만족하기 위하여 대체연료의 하나인 LPG에 대한 수요가 증가하고 있다. 현재 LPG 차량에 적용되고 있는 제3세대 LPG 연료공급방식인 LPLi(Liquid Phase LPG Injection) 시스템은 가솔린 차량과 비교하여 배출가스는 적게 배출하면서 동등한 출력을 낼 수 있게 하는 핵심 기술이다. LPG 연료를 고압의 액상 상태로 공급하기 위해서는 LPG 펌프가 필요하다. 연료펌프의 성능을 저하 시킬 수 있는 연료 내 불순물을 제거하기 위하여 연료펌프에는 연료필터가 장착되어 있으며 장착되는 연료필터의 종류에 따라서 연료펌프의 성능도 변하게 된다. 본 연구에서는 임펠라 방식을 채택한 LPG 연료펌프에서 극세사, 이중메쉬, 외장형 필터의 세 가지 필터에서 부하별 토출성능 및 효율을 파악하였으며 온도 변화에 따른 펌프유량 변화를 측정하였다.

• 한국수소및신에너지학회논문집
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• 제22권5호
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• pp.678-685
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• 2011

An Ejector enhances system efficiency, are easily operated, have a mechanically simple structure, and do not require a power supply. Because of these advantages, the ejector has been applied to a variety of industrial fields such as refrigerators, power plants and oil plants. In this work, an ejector was used to safely recycle anode tail gas in a 75-kW Molten Carbonate Fuel Cell (MCFC) system at KEPCO Research Institute. In this system, the ejector is placed at mixing point between the anode tail gas and the cathode tail gas or the fresh air. Commercial ejectors are not designed for the actual operating conditions for our fuel cell system. A new ejector was therefore designed for use beyond conventional operating limits. In the first place, a few sample ejectors were manufacured and the entrainment ratio was measured at a dummy stack. Through this experiment, the optimum ejector was chosen. The 75-kW MCFC system equipped with this optimum ejector was operated successfully.