• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.8
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• pp.2015-2020
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• 2009

$NO_x$ reduction of stationary exhaust was performed at atmospheric condition and the temperature ranging from $200^{\circ}C$ to $500^{\circ}C$ over ZSM-5 supported metal catalyst. The characteristics of the prepared catalysts were investigated using the analytical techniques such as SEM, XRD, EDX, ICP and ITR. The results of EDX and ICP analysis demonstrated that the most part of transition metal existed on the exterior surface of support. Maximum de-$NO_x$ yield over Fe/ZSM-5 shown between $380^{\circ}C$ and $400^{\circ}C$ was presumed to be due to the maximum H2 reduction rate at $400^{\circ}C$ of ITR.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.100-103
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• 2012

The blending method that is an addition of small quantity of fuel was used to increase the performance of green propellant thruster. 90 wt.% hydrogen peroxide as a green propellant was selected, and ethanol was used as a blended fuel. The o/f ratio was chosen as 50 which has higher theoretical performance than 98 wt.% hydrogen peroxide. The chamber temperature of blended hydrogen peroxide was higher than adiabatic chamber temperature of hydrogen peroxide. Therefore, performance can be improved by ethanol blending. Several catalyst and its support were compared to find appropriate catalyst for decomposition and combustion of ethanol blended hydrogen peroxide. As a experimental results, Pt was suitable, but $MnO_2$ had a chamber instability when it was reused. The ${\alpha}-Al_2O_3$ which is high heat-resistant support showed very unstable performance in both Pt and $MnO_2$ catalyst since it has low decomposition performance.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.85-88
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• 2011

In the trend of world wide environment preservation, researchers tried to find new environment friendly propellant instead of highly toxic propellant, Hydrazine. Among the candidates, ionic liquid propellants have lower toxicity, higher density, and higher specific impulse than Hydrazine. These ionic liquid propellants have high combustion chamber temperature, so catalyst supports such as gamma alumina cannot withstand in that temperature. Therefore, a catalyst that showed stable characteristic in high temperature is needed. Barium dopped alumina can be changed to Hexaaluminate in high temperature, and its characteristic in high temperature is superior than gamma alumina. Barium dopped Alumina is wet impregnated with Platinum and heated up to $1300^{\circ}C$ and $1400^{\circ}C$ for 2 hours. Those catalysts were examined by XRD, SEM, EDS, BET, and Drop test.

• 한국연소학회:학술대회논문집
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• 2004.11a
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• pp.217-222
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• 2004

In recent year, as the current and future emission regulations go stringent, the research of exhaust manifold and CCC has become the subject of increasing interest and attention. This study is concerned with the systematic approach to improve catalyst flow uniformity and light-off behavior through the basic understanding of exhaust flow characteristics. Computational approach to the unsteady compressible flow for exhaust manifold of 4-1 type and 4-2-1 type and CCC system of a 4-cylinder DOHC gasoline engine was performed to investigate the flow distribution of exhaust gases. In this study, through calculation, the effects of geometric configuration of exhaust manifold on flow structure and its maldistribution in monolith were mainly investigated to understand the exhaust flow patterns in terms of flow uniformity. Based on the design guidance resulting from this fundamental study, the flow uniformity of 4-2-1 type exhaust manifold demonstrated the more improved exhaust characteristics than that of the 4-1 type one.

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.355-356
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• 2014

Catalytic steam reforming of tar produced from biomass gasification was conducted using several Ni-based catalysts. K and Mn were used as a promoter over $Ni/Ru/Al_2O_3$ catalyst. The pellet and monolith type catalysts were prepared and applied to lab and bench-scale biomass gasification system. The $Ni/Ru-K/Al_2O_3$ catalyst shown higher performance than $Ni/Ru-Mn/Al_2O_3$ catalyst at low temperature range.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1997.04a
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• pp.191-201
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• 1997

혼합형 고체추진제에는 연소속도를 증가시키는 촉매로서 철,구리,크롬등 전이금속 $화합물^1$ 이 사용되고 있다. 현재 당공장에서 양산되는 개량형 추진기관의 추진제에 철화합물인 $Fe_2$ $O_3$ 가 사용되는데 그동안 $Fe_2$ $O_3$ 를 공급해온 미국 Columbian chemical co.에서 생산을 중단함에 따라 새로운 수급이 필요하게 되었다. 이에 이원료의 안정적인 공급을 위해 국산 $Fe_2$ $O_3$ 로 대체 개발하기 위해 국산 원료의 시장조사, 샘플 입수, 그리고 원료분석을 실시하였지만 당공장에서 사용해온 $Fe_2$ $O_3$ 의 원료규격중 순도, 산도(PH값), 입도등 중요항목을 만족할만한 국산 원료는 발견하지 못했다. 하지만 국내 제조업체중 제조능력 및 시설을 고려하여 일신종합화학(인천 소재)을 선정한 다음 제조 공정의 개선을 통하여 당공장 사용 원료을 만족하는 원료를 생산할 수 있었고, 개향형 추진 기관의 추진제에 적용하여 추진제 공정성, 물성, 그리고 가장 중요한 연소특성을 만족하는 국산 $Fe_2$ $O_3$ 를 개발에 성공하여 양산에 적용하고 있다.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2000.11a
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• pp.19-24
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• 2000

수소 연료는 공해물질을 전혀 배출하지 않고 수송용 및 연료전지 등에 널리 사용되므로 21세기의 궁극에너지로 인식되고 있다. 수소가 미래의 궁극적인 대체에너지원 또는 에너지 매체로 꼽히고 있는 것은 현재의 화석연료나 원자력 등이 따를 수 없는 장점을 갖고 있기 때문이다. 또한 수소는 연소시 극소량의 질소가 생성되는 것을 제외하고는 공해물질이 배출되지 않으며, 직접 연소를 위한 연료 또는 연료전지 등의 연료로 사용이 간편하다. 그러나, 기존의 수소제조 기술은 화석연료 중의 탄소 성분을 물과 반응시켜 수소로 만들기 때문에 상당량의 에너지가 필요하고 이 반응은 흡열반응이기 때문에 탄소 성분을 가스화 시키기 위해서는 1300K 이상의 고온과 상당한 반응기 용량이 요구된다.(중략)

• Journal of the Korean Society of Industry Convergence
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• v.1 no.2
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• pp.49-54
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• 1998

In the catalytic combustor, combustion characteristic and deterioration of catalysts were affected by non-uniformity of pre-mixed gas, Therefore, formation of uniform pre-mixed gas is one of important subjects. In this study, the effect of uniformity and non-uniformity of pre-mixed gas supplied to the catalyst was examined to clarify reaction acceleration and combustion characteristic of the catalytic combustion. It was clarified that static mixer or vaporizer tube length of about 150mm and weak swirl to a combustion air were effictive expedient to make uniform pre-mixed gas. And catalystic inlet temperature needs more than $600^{\circ}C$ with rich pre-mixed gas to active reaction.

• Journal of the Korean Society of Combustion
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• v.2 no.1
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• pp.29-38
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• 1997

In this study, the experimental and numerical investigations of the ignition of methane-air mixtures by a electrically heated wire have been carried out. In order to define the initial condition and make the analysis simple, the following control unit was developed; which heats the wire to the setting temperature in a very short time, and maintains the wire temperature constant until ignition. Experiments with the feedback control have been performed using nickel and platinum wires in normal gravity and microgravity. From experimental results, ignition temperatures in normal gravity are higher than those in microgravity, however, the dependences of ignition temperature on equivalence ratio are not affected by natural convection. Numerical calculations, including catalytic reaction for platinum, have been performed to analyze the experimental results in microgravity. Numerical results show that reactants near platinum wire are consumed by catalytic reaction, therefore, the higher temperature is needed to ignite the mixture with platinum wire.

• Journal of the Korean Society of Combustion
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• v.8 no.2
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• pp.50-55
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• 2003

Synthesis of carbon nanofibers on a metal substrate by an ethylene fueled inverse diffusion flame was observed. Stainless steel plates were used for the catalytic metal substrate. The effects of radial distance and residence time of the substrate were investigated. The role of hydrocarbon composition in the fuel was also viewed. Nanofibers with a diameter range of 30-70nm were found on the substrate. The carbon nanofibers were formed and grown in the region from 4 to 5.5mm from the central axis of a flame outside of the visible flame front in the radial direction. The minimum residence time required for the formation of carbon nanofibers were about 20 seconds, and over 60 seconds were required for the full-scale growth. The characteristic time of the formation of carbon nanofibers was much shorter than that of the substrate temperature growth. In this study, the variation in hydrocarbon composition had no significant effect on the formation and growth of the carbon nanofibers.