• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.115.2-115.2
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• 2010

Autothermal reforming(ATR) processes of hydrocarbon liquids such as diesel fuels are spotlighted as methods to produce hydrogen for Fuel cell. However, the use of heavy hydrocarbons as feedstocks for hydrogen production causes some problems which increase the catalyst deactivation by the carbon deposition. Coking can be inhibited by increasing the water dissociation on the catalyst surface. This results in catastrophic failure of whole system. Performance degradation of diesel autothermal reforming leads to increase of undesirable hydrocarbons at reformed gases and subsequently decrease the performance. In this study, perovskite-based catalysts were investigated as alternatives to substitute the noble metal catalyst for the ATR of diesel. The investigated perovskite structure was based on LaCrO3. and metals were added at the A-site to enhance oxygen ion mobility, transition metals were doped on the B-site to enhance the reformation. Substituted Lanthanum chromium perovskite were made by aqueous combustion synthesis, which can produce high surface area. And for the homogeneous fuel supply, we made ultrasonic injection system for reforming. We compared durability of evaporation system and ultrasonic system for fuel injection.

• 융복합기술연구소 논문집
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• 제10권1호
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• pp.19-24
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• 2020

The purpose of the study is to investigate the thermal durability characteristics of the Pt catalyst and additives used in a catalytic combustor. The catalyst used in the experiment was based on Pt (3 wt%), and a total of 12 types were prepared using a combination of additives (Ni, La, Ce, Fe, and Co). From the results, In the fresh state, the two types of combination catalysts with the highest C₃H₈ conversion were Pt_Ce (79.9%) at 500℃, and in the three types of combination catalysts, Pt_La_Ni (93.4%) at 500℃ had the best performance. Among aged catalysts at 850℃ and 8 hours, Pt-La-Ni and Pt-Ni-Ce catalysts showed the highest C₃H₈ conversion of about 71% at 500℃.

• International Journal of Automotive Technology
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• 제2권2호
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• pp.63-75
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• 2001

This paper describes the development of THC reduction technologies compliant with SULEV regulations. Technologies embodied by the developmental work include improvement of fuel spray atomization, quick warm-up through coolant control shut of, and acceleration of fuel atomization for the fast rise of cylinder head temp inside the water jacket as well as the improvement of combustion state. The technologies likewise entail reduced HC while operating in lean A/F condition during engine warm-up with the cold lean burn technology, individual cylinder A/F control for improvement of catalytic converting efficiency, after-treatment such as thin-wall catalyst, HC-adsorber and EHC and etc, through vehicle application evaluation in cold start. We carried out an experimental as well as a practical study against SULEV regulations, and the feasibility of adopting these items in vehicle was likewise investigated.

• Bulletin of the Korean Chemical Society
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• 제35권8호
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• pp.2257-2262
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• 2014

$C_{60}$ is widely investigated because of its unique structure. But its applications in solid propellant seem to be relatively neglected. $C_{60}$ has more outstanding features than carbon black which is widely used as a catalyst ingredient of solid propellant. To combine the advantages of fullerene and lead salts, another good composite in propellant catalysts, we synthesized a kind of fullerene phenylalanine lead salt (FPL) and explored its thermal performances by differential thermal analysis (DTA) and thermogravimetry analysis (TGA). The results show it undergoes four exothermic processes started from 408 K. Combined TGA and X-ray diffractometer (XRD), the decomposition mechanism of FPL was derived by TG-IR and comparing IR spectra of FPL and its residues after burned to $327^{\circ}C$, $376^{\circ}C$ and $424^{\circ}C$, respectively. Effect of FPL on the decomposition characteristic of hexogen (RDX), a type of explosive in propellant, has been investigated using DTA at different heating rate, which shows the decomposition temperatures of the explosive are all reduced by more than 20 K. The corresponding activation energy ($E_a$) is decreased by $30kJ{\cdot}mol^{-1}$. So FPL has potential application as a combustion catalyst in solid propellant.

• 한국자동차공학회논문집
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• 제17권3호
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• pp.81-89
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• 2009

In this experimental study, the effects of clean alternative fuels compatible with diesel combustion on nano-sized particle emission characteristics were investigated in a 0.5L auto-ignited single-cylinder engine with a compression ratio of 15. Because the number concentration of nano-sized particles emitted by automotive engine, that are suspected of being hazardous to human health and environment, might increase with engine fuel considerably and recently attracted attention. So a ultra-low sulfur diesel(ULSD), BD100(100% bio-diesel) and Di-Methyl Ether(DME) fuels used for this study. And, as a particle measuring instrument, a fast-response particle spectrometer (DMS 500) with heated sample line was used for continuous measurement of the particle size and number distribution in the size range of 5 to 1000nm (aerodynamic diameter). As this research results, we found that this measurements involving the large proportion of particles under size order of 300nm and number concentration of $4{\times}10^9$ allowed a single or bi-modal distribution to be found at different engine load conditions. Also the influence of oxygen content in fuel and the catalyst could be a dominant factor in controlling the nano-sized particle emissions in auto-ignited engine.

• 한국추진공학회지
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• 제22권2호
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• pp.29-37
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• 2018

5 N 급 단일추진제 추력기를 이용하여 ADN 기반 고성능 친환경 단일추진제의 연소 시험을 수행했다. ADN 기반 추진제 및 촉매의 제작을 진행했으며, DSC-TG 분석을 통한 검증을 진행했다. 연소 시험 시 촉매 반응기 내에서 작은 규모의 연소 불안정 현상이 발생했지만, 촉매 반응기 전단에서의 높은 온도를 관찰하여 제작된 추진제의 촉매 연소가 발생했음을 파악했다. 향후 보다 높은 열적 안정성을 확보하기 위해 추진제의 높은 단열 분해 온도를 견딜 수 있는 촉매의 개발을 수행하고 이를 적용할 예정이다.

• 한국자동차공학회논문집
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• 제15권1호
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• pp.162-170
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• 2007

Currently, due to the serious world-wide air pollution by substances emitted from vehicles, emission control is enforced more firmly and it is expected that the regulation requirements for emission will become more severe. Anew concept combustion technology that can reduce the NOx and PM in relation to combustion is urgently required. Due to such social requirement, technologically advanced countries are making efforts to develop an environment-friendly vehicle engine at the nation-wide level in order to respond to the reinforced emission control. As a core combustion technology among new combustion technologies for the next generation engine, the homogeneous charge compression ignition (HCCI) is expanding its application range by adopting multiple combustion mode, catalyst, direct fuel injection and partially premixed combustion. This study used a 2-staged injection method in order to apply the HCCI combustion method without significantly altering engine specifications in the aspect of multiple combustion mode and practicality by referring to the results of studies on the HCCI engine. And it is investigated that the effects of the engine rpm and load(or A/F) to emission characteristics.

• 청정기술
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• 제19권2호
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• pp.128-133
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• 2013

$CeO_2$에 담지된 구리산화물에서 벤젠의 촉매연소 반응에 대해 연구하였다. 담지된 구리산화물 촉매들은 볼밀법과 함침법으로 제조하였고, XRD, FT-IR, TEM 및 TPR에 의해 특성분석을 하였다. 볼밀법으로 제조된 CuO/$CeO_2$ 촉매는 높은 담지량에서도 잘 분산된 CuO를 얻었다. 볼밀법으로 제조된 CuO/$CeO_2$ 촉매는 함침법으로 제조된 촉매에 비해 높은 활성을 보여주었다. CuO의 담지량이 증가할수록 촉매 활성이 증가하였으며, 10 wt%로 담지된 촉매에서 가장 높은 활성을 나타내었다. 또한, 10 wt% CuO/$CeO_2$ 촉매에 소량의 $Fe_2O_3$와 CoO의 조촉매 첨가는 CuO의 분산도를 높여 반응활성을 증가시켰다.

• 한국수소및신에너지학회논문집
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• 제31권1호
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• pp.82-88
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• 2020

Recently, a fuel reforming plant for supplying high purity hydrogen has been studied to increase the operation time of underwater weapon systems. Since steam reforming is an endothermic reaction, it is necessary to continuously supply heat to the reactor. A fuel reforming plant needs a methanol-O₂ catalytic burner to obtain heat and supply heat to the reformer. In this study, two types of designs of a catalytic burner are presented and the results are analyzed through the experiments. The design of the catalytic burner is divided into that the O₂ supply direction is perpendicular to the methanol flow direction (Design 1) and the same as the methanol flow direction (Design 2). In case of Design 1, backfire and flame combustion occurred in the mixing space in front of the catalyst, and in the absence of the mixing space, combustion reaction occurred only in a part of the catalyst. For above reasons, Design 1 could not increase the exhaust gas temperature to 750℃. In Design 2, no flashback and flame combustion were observed, the exhaust gas could be maintained up to 750℃. However, the O₂ distributor was exposed to high temperatures, resulting in thermal damage.

• 한국추진공학회지
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• 제23권3호
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• pp.1-8
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• 2019

아산화질소($N_2O$) 열분해를 위해 아크 플라즈마를 이용한 점화 실험을 수행하였다. 기존의 점화기들은 신뢰성 및 즉각적인 응답을 얻기 어렵다는 단점을 해결하기 위한 방안으로 플라즈마를 활용하는 방안을 제시하고자 하며, 점화기로써의 가능성을 보기 위해 가스 온도 측정 및 연소 실험을 수행하였다. 1 g/s, 0.7 A 조건에서 가장 안정적인 방전 특성을 보였으며 이때 측정된 벽면 부근의 온도는 약 $960^{\circ}C$이었다. 이를 바탕으로 하이브리드 로켓 연소 실험을 수행하였다. 플라즈마 방전 이후 약 3.1 sec만에 총 유량 10 g/s의 메인 연소가 성공적으로 이루어졌으며 점화에 필요한 플라즈마 발생을 위한 에너지 소모량은 1,780 J이었다.