• Bulletin of the Korean Space Science Society
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• 2007.10a
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• pp.107.2-107.2
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• 2007

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1998.10a
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• pp.9-9
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• 1998

다목적 실용위성의 궤도전이 및 위성체 자세제어를 위한 추진시스템의 설계요소에는 구조적 안전성, 우주환경에서의 열제어를 위한 회로 및 구성하드웨어 설계, 연료계통 맥압강하를 위한 장치설계 및 추력기 배기가스 영향을 고려한 형상설계 등이 있으며, 설계검증을 위해 부분해석이 수행된다. 또한 발사환경과 우주 궤도환경에서의 추진시스템 성능평가를 위한 연제어계 기능시험, 압력인증시험, 청정도시험 및 내부/외부 누설시험이 수행된다. 본 논문에서는 추진시스템 설계 및 조립공정에 대해 기술하였고, 시험분석을 통해 시스템의 설계 및 조립공정상의 신뢰성을 검증 분석하였다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.04a
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• pp.179-182
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• 2007

The new KOMPSAT in preliminary design phase will utilize 4.45 N monopropellant thrusters for attitude and orbit control. In this paper, a numerical plume analysis is performed to verify the effects of thruster plume on the satellite with a 3-D satellite base region model by DSMC. As a result, plume behaviors such as overall plume temperature, total density and thermal radiation to solar array are estimated.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.1
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• pp.117-124
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• 2003

Thermal design fur satellite propulsion system has been performed. Overall design requirements and the constitution for propulsion system is described. To meet the thermal design requirements, both a primary and a redundant heater circuit, each with two thermostats placed in series, will protect each hydrazine-wetted components, even if one heater circuit fails to operate. Heater power is turned off if any one of these thermostats is opened at its higher setpoint. Thus, even if one thermostat is failed closed, the second thermostat will turn off the heater. All such components shall be insulated with MLI. Propulsion heater sizing based on the constant worst cold case condition is conducted through thermal analysis. All heaters selected fur propulsion components operate to prevent propellant freezing satisfying the thermal requirements for the propulsion subsystem over the worst case average voltage, i.e. 25 volts.

• Journal of computational fluids engineering
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• v.10 no.3 s.30
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• pp.63-69
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• 2005

The COMS, the first meteorological geostationary satellite in Korea, is under development by KARI. The radiator size and the heater power for the thermal control of COMS are calculated using an analytic method. The total radiator area of $4.85\;m^2$ and the total heater power of 794.77 W are determined at a conceptual design of COMS. The commercial software, SINDA and TRASYS, are utilized in order to compare and verify the analytic results. The results of on-orbit numerical simulation of cold and hot cases show that the radiator size and heater power obtained from the analytic method are appropriate to maintain COMS equipments within required temperature ranges.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.2
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• pp.150-157
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• 2014

Li-Ion battery is used in the most satellites now due to advantages such as weight, thermal dissipation and self discharge compared to the previous generations of electrochemical batteries. The performance analysis model of the Li-Ion battery is needed to aid the design of new satellite electrical power subsystem. This paper develops the performance analysis model of the Li-Ion battery to apply to the electrical power subsystem design and energy balance analysis on geostationary orbit. The analysis model receives the satellite bus power, solar array power and battery temperature and gives the battery voltage, charge and discharge currents, taper index, state of charge and power dissipation. The results from the performance analysis are compared and analyzed with the flight data to verify the model. The compared results show satisfactory without significant difference with the flight data.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.7
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• pp.126-132
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• 2004

Thermal control of satellite propellant tank is achieved by patch heaters enabled by thermostat's behavior. It is important to attach the thermostat on the appropriate position of the propellant tank. However its position cannot be given with exact numerics because tank is spherical. In practice, the thermostat position is designated approximately in a relevant drawing approximately, thereby an engineer practices depending on his own experience and intuition. The sensitivity analysis for the position of thermostat is performed such that the influence on the thermal behavior and control of tank is examined quantatively. When assembling tank module, the reasonable performance on the thermal control is believed with possible human errors if the uncertainty in the position of thermostat is not quite large.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.164.2-164.2
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• 2012

인공위성레이저추적(SLR, Satellite Laser Ranging) 시스템은 인공위성까지 레이저를 발사하여 되돌아오는 시간간격을 측정함으로서 위성까지의 거리를 측정하는 시스템으로 현존하는 인공위성 궤도결정 시스템으로는 가장 정밀하다. 한국천문연구원은 우주추적 및 감시의 필요성이 증가함에 따라 2008년부터 40cm급 이동형 인공위성레이저추적 시스템을 개발을 시작하였고, 현재 개발을 완료하여 시험운영 중에 있다. 시스템 개발 과정 중에 발생할 수 있는 문제점들을 최소화하기 위해, 설계 단계에서 부품을 포함한 광기계 구조물에 대한 구조해석과, 실험실 프로토타입 구성 등을 실시하였다. 제작된 각 서브시스템별 조립 및 평가는 한국천문연구원이 보유한 광학계 조립 및 평가 시설을 이용하였다. 개발된 이동형 레이저 추적 시스템의 광학부는 추적마운트에 장착되었고, 현장 시험관측을 통해 수신광학계 및 광신호유도계의 정렬 및 제어항목 교정 등을 실시하였으며, 성공적으로 시험 영상 관측을 완료하였다. 이 발표에서는 이동형 레이저 추적 시스템 광학계의 개발 과정과 그 결과에 대해 보고한다.

• Bulletin of the Korean Space Science Society
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• 2007.10a
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• pp.112-112
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• 2007

• 한국전산유체공학회:학술대회논문집
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• 2011.05a
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• pp.230-235
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• 2011

COMS (Communication, Ocean and Meteorological Satellite) is a geostationary satellite and was developed by KARI for communication, ocean and meteorological observations. COMS was tested under vacuum and very law temperature conditions in order to correlate thermal model and to verify thermal design. The test was performed by using KARI large thermal vacuum chamber. The COMS S/C thermal model was successfully correlated versus the 2 thermal balance test phases. After model correlation, temperatures deviation of all individual unit were less than $5^{\circ}C$ and global deviation and standard deviation also satisfied the requirements, less than $2^{\circ}C$ and $3^{\circ}C$. The final flight prediction was performed by using the correlated thermal model.