• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1998.04a
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• pp.31-31
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• 1998

위성체의 보조추진시스템은 임구궤도까지의 궤도진입 및 임무궤도상에서의 속도 또는 자세제어에 필요한 임펄스를 제공한다. 단일하이드라진 추력기는 하이드라진(H$_2$H$_4$)과 자발적 촉매(Shell 405)의 발열 및 흡열 열분해 반응에 의해 발생하는 질소($N_2$), 수소(H$_2$), 암모니아(NH$_3$), 혼합가스를 노즐을 통해 방출하므로써 요구되는 impulse를 얻는다. 단일하이드라진 추력기 설계는 주입기, 촉매대, 노즐과 기타 설계 형태에 따른 다지관, 링, 스크린, 지지판 등의 부수적인 부품으로 구성된다. 추력기 제작 과정은 크게 piece-parts 기계가공, HEA(Head End Assembly)와 TCA(Thrust Chamber Assembly)로 구성되고 각 세부공정마다 전수시험 및 검사를 가진다. 연소시험설비는 최소 모사진 공 수준이 고도 100,000 ft(8.4 torr)를 만족시킬 수 있는 진공설비, 시험제어부, 성능변수 측정 및 처리부, 추진제 가압 공급부, 기타 환경 안전 및 부대 설비로 구성된다. 추력기 연소성능시험 절차는 추진제 충전 및 오염 여부 표본 검사, 가압 및 공급 라인 이상여부 확인, 추력기 장착, 추진제 가압 및 공급, 시험장치 보정, 진공 모사 및 연소성능시험, data 처리 등으로 구성된다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.641-647
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• 2017

In order to meet the stricter emission regulations, the proportion of after-treatments for vehicles and vessels has been increasing gradually. The objective of this study is to investigate the physicochemical properties according to ash cleaning agents of CDPF for Diesel Engines. Penetrating agents with strong penetration into ash and a surfactant component to mix water and oil were prepared properly. The cleaning characteristics of S1 sample were good. Washcoat loss rate of S1 sample was lower by about 2.2% because of less KOH component and lower Na2SiO3 content. Washcoat loss rate of S4 sample with an added KOH and Na2SiO3 components by penetration agents was increased by about 13%. In terms of less than about 13% of CDPF's washcoat loss rate, it was able to reduce the harmful gas components.

• Korean Chemical Engineering Research
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• v.49 no.5
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• pp.633-638
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• 2011

Mn substituted La, Sr or Ba-hexaaluminate were prepared by $(NH_4)_2CO_3$ co-precipitate method and calcined at $1,200^{\circ}C$ for 5 h. Catalysts were characterized by X-ray diffraction and $N_2$ physisorption and scanning electron microscope (SEM). Compared to $SrMnAl_{11}O_{19}$ and $BaMnAl_{11}O_{19}$, $LaMnAl_{11}O_{19}$ in which La located at mirror plane showed better crystallinity and high surface area, 13 $m^2/g$. $LaMnAl_{11}O_{19}$ revealed well developed plate-like structure which is characteristic structure of hexaaluminate. The catalytic activity of methane combustion increased in the following order: $LaMnAl_{11}O_{19}$ > $SrMnAl_{11}O_{19}$ > $BaMnAl_{11}O_{19}$ and was dependent on surface area of catalysts. 60 wt% $CeO_2/LaMnAl_{11}O_{19}$ calcined at $700^{\circ}C$ showed enhanced methane activity and methane was oxidized completely at low temperature ($700^{\circ}C$). It was confirmed that addition of ceria seems to be effective for the low and middle temperature combustion of methane. But, after calcination at high temperature of $1,200^{\circ}C$, it lost the promoting effect of ceria due to increase of ceria particle size and it had a limit to applying to the high temperature catalytic combustion.

• 보일러설비
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• s.81
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• pp.101-102
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• 2000

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2000.04a
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• pp.299-302
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• 2000

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2001.04a
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• pp.109-109
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• 2001

• Korean Chemical Engineering Research
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• v.56 no.5
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• pp.752-760
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• 2018

The lowering of temperature for combustion of diesel particulate matters (or diesel soot) is one of the important tasks in automotive industry that is searching for a way to meet up "high-fuel efficiency, low-emission" standard. In this study, it was discussed how the use of ozone over platinum-based catalyst promotes a low-temperature soot oxidation occurred at $150^{\circ}C$. The use of platinum catalyst did not increase oxidation rate largely but was very effective in improving the selectivity of carbon dioxide. The pre-oxidation of NO into $NO_2$ using ozone was rather crucial in improving the oxidation rate of soot at $150^{\circ}C$.

• 한국연소학회:학술대회논문집
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• 2003.12a
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• pp.299-308
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• 2003

This paper provides a review of the status and of the perspectives of advanced catalytic combustion for ultra clean combustion of gas turbines and for industrial combustors. The development of catalytic materials and their combustion techniques for gas turbines are briefly reported. The fuel-rich approaches to catalytic combustion are mentioned for a new technology of thermal- and fuel-NOx control. The fuel-rich catalytic combustion are also applicable to the combustor of ceramic gas turbine, and to the combustion of biomess and municipal waste sludge. Some extended technologies of combustion synthesis are introduced for the synthesis of carbon nanotube and of Perovskite combustion catalysts

• Journal of the KSME
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• v.28 no.5
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• pp.469-475
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• 1988

연료소비율의 향상은 점차 감소되어 가는 경향에 있다. 그 원인은 3원촉매변환기 채용에 의한 이론공기연료비의 사용, 기관의 연소개선이 발전하여 고압축비화에 의한 연료소비율 향상이 더 이상 어렵게 되었다는 점을 들 수 있다. 한편, 고압축비화의 역효과로는 연소실내 최고압력이 증가하여 각부의 강도나 기관 소음의 문제가 대두된다. 이들 역효과를 타파하여 충분한 연료 소비 향상을 얻을 수 있는 수단이 단기적인 과제가 될 것이다. 전자제어, 희박연소, 마찰저감 등 통상의 엔진의 개량에 대한 노력이 계속될 것이다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.218-222
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• 2011

During the development of the iridium catalyst for domestic production, the catalyst failure, loss, sintering phenomena are observed by high pressure and temperature. By these abnormal failure of catalyst bed, the performance of thruster is degraded. To figure out the detail phenomena on the damaged catalyst bed, a numerical analysis code is developed by assuming the catalyst bed as an one dimensional porous media. The numerical analysis code is validated with experiment data. Thereby, resulting physical phenomena are examined by considering the variation of catalyst bed characteristics incurred by catalyst granule failure. Through these numerical analyses we figure out the effect of the catalyst loss on the decomposition of hydrazine and ammonia.