• Title/Summary/Keyword: Satellite propulsion

Search Result 211, Processing Time 0.041 seconds

정지궤도 인공위성 추력기 모델링

  • Park, Eung-Sik;Park, Bong-Kyu
    • Aerospace Engineering and Technology
    • /
    • v.2 no.2
    • /
    • pp.96-104
    • /
    • 2003
  • Geostationary satellite propulsion system provides satellite with the velocity increment for attitude control operations and sationkeeping operations from satellite launch to de-orbit at the end of life. Today, various types of propulsion system and its thrusters are produced by worldwide manufactures. Therefore, geostationary satellite manufacturers give significant modification to the Mission Analysis Software whenever different type of propulsion system type is adopted. Mission Analysis Software is a tool for planning and verification of satellite mission. For the development of the Generalized Mission Analysis Software, many thrusters are carefully investigated and modeled.

  • PDF

Transient Flow Behavior of Propellant with Actuation of Thrust Control Valve in Satellite Propulsion System (위성 추진시스템의 추력제어밸브 작동에 따른 추진제 비정상 유동 특성)

  • Kim, Jeong-Soo;Han, Cho-Young;Choi, Jin-Chul
    • Proceedings of the KSME Conference
    • /
    • 2001.06e
    • /
    • pp.294-298
    • /
    • 2001
  • Satellite propulsion system is employed for orbit transfer, orbit correction, and attitude control. The monopropellant feeding system in the low-earth-orbit satellite blowdowns fuel to the thrust chamber. The thrust produced by the thruster depends on fuel amount flowed into the combustion chamber. If the thruster valve be given on-off signal from on-board commander in the satellite, valve will be opened or closed. When the thrusters fire fuel flows through opened thruster valve. Instantaneous stoppage of flow in according to valve actuation produces transient pressure due to pressure wave. This paper describes transient pressure predictions of the KOMPSAT2 propulsion system resulting from latching valve and thrust control valve operations. The time-dependent set of the fluid mass and momentum equations are calculated by Method of Characteristics (MOC).

  • PDF

Preliminary Design of LEO Satellite Propulsion System (저궤도위성 추진시스템 예비 설계)

  • Yu, Myeong-Jong;Lee, Gyun-Ho;Kim, Su-Gyeom;Choe, Jun-Min
    • Aerospace Engineering and Technology
    • /
    • v.5 no.2
    • /
    • pp.85-89
    • /
    • 2006
  • Propulsion System provides the required velocity change impulse for orbit transfer from parking orbit to mission orbit and three-axis vehicle attitude control impulse. New LEO Satellite propulsion system (PS) will be an all-welded, monopropellant hydrazine system. The PS consists of the subassemblies and components such as Thrusters, Propellant Tank, Pressure Transducer, Propellant Filter, Latching Isolation Valves, Fill/Drain Valves, interconnecting propellant line assembly, and thermal hardwares for operation-environment control of the PS. In this study, preliminary design process of LEO Satellite propulsion system will be summarized.

  • PDF

정지궤도위성 추진시스템 온도추이를 통한 위성폐기 가능시점 연구

  • Park, Eung-Sik;Han, Cho-Young
    • Aerospace Engineering and Technology
    • /
    • v.4 no.2
    • /
    • pp.94-100
    • /
    • 2005
  • The geostationary satellite propulsion system has thermistors which can measure liquid propellant temperature at tanks, pipes and etc. In the satellite propulsion system with several tanks, the propellant in the tanks is moved by temperature change and this temperature pattern is constant. In this paper, the temperature change pattern of KOREASAT 1 propulsion system is compared and the prediction study of pressurant inflow using temperature change of geostationary satellite propulsion system is described.

  • PDF

A STUDY ON THERMAL MODEL REDUCTION AND DYNAMIC RESPONSE (열해석 모델 간략화 및 동적특성에 관한 연구)

  • Jun, Hyoung Yoll;Kim, Jung-Hoon
    • Journal of computational fluids engineering
    • /
    • v.19 no.4
    • /
    • pp.37-44
    • /
    • 2014
  • A detailed satellite panel thermal model composed of more than thousands nodes can not be directly integrated into a spacecraft thermal model due to its node size and the limitation of commercial satellite thermal analysis programs. For the integration of the panel into the satellite thermal model, a reduced thermal model having proper accuracy is required. A thermal model reduction method was developed and validated by using a geostationary satellite panel. The temperature differences of main components between the detailed and the reduced thermal model were less than $1^{\circ}C$ in steady state analysis. Also, the dynamic responses of the detailed and the reduced thermal model show very similar trends. Thus, the developed reduction method can be applicable to actual satellite thermal design and analysis with resonable accuracy and convenience.

Unsteady Flow Analysis of Liquid Hydrazine Propellant for the Design Parameter Derivation of Satellite Propulsion System (인공위성 추진기관 설계변수 도출을 위한 Hydrazine 액체 추진제의 비정상 유동해석)

  • Choi, Jin-Chul;Kim, Jeong-Soo
    • Proceedings of the KSME Conference
    • /
    • 2000.11b
    • /
    • pp.497-501
    • /
    • 2000
  • One of the way to derive design parameters of the fuel feeding system in satellite is to analyze unsteady flow of liquid propellant (hydrazine) in the propulsion system. During steady thruster firing the flow rate is constant: if a thruster valve is abruptly shut down among a sets of thrusters, pressure spikes much higher than the initial tank pressure occur. This renders the fuel flow unsteady, and the fluid pressure and flow rate to oscillate. If the pressure spikes are high enough, there are possibilities that propellant explosively decomposes, thruster valves are damaged, and adiabatic detonation of the hydrazine propellant is potentially incurred. Reflected shockwaves could also affect the calibration and operation of the pressure transducers. These necessitate the analysis of unsteady flow in the propulsion system design, and the calculation results obtained through some governing parameter variation are presented in this work.

  • PDF

A Development of Solenoid Valve for Satellite Propulsion System (위성추진시스템 솔레노이드 밸브 개발)

  • Kim, Kyung-Sik;Baek, Ki-Bong;Park, Eun-Joo;Cho, Seung-Hwan;Kim, Su-Gyeom
    • Proceedings of the Korean Society of Propulsion Engineers Conference
    • /
    • 2011.11a
    • /
    • pp.456-459
    • /
    • 2011
  • The Dual-type Solenoid Valve was developed for a domestic production of a fuel-supply valve on the satellite attitude control thruster system. The satellite valve using a hydrazine as a fuel must fulfill the cycle life, shock, vibration and the environment of an extremely low temperature In addition to the basic performance of the response time, mass flow and leakage etc.. in this paper, the design, production and performance experiment using the nitrogen pneumatic equipment were conducted.

  • PDF

A Study on the Application of a Fully Electric Propulsion System for Geostationary Missions (정지궤도위성의 완전 전기추진시스템 적용방안 연구)

  • Choi, Jaedong;Park, Bongkyu
    • Journal of Aerospace System Engineering
    • /
    • v.16 no.5
    • /
    • pp.26-34
    • /
    • 2022
  • The propulsion system of geostationary orbiting satellites is typically used to raise the orbit into a transfer orbit, maintain the orbital position in the south/north, east/west direction in regular operation, and accumulate momentum in the south/north and east/west direction. Recently, when an electric propulsion system is used in a geostationary orbit satellite, the payload capacity can be increased by about 40% compared to a chemical propulsion system. However, despite these advantages, using an electric propulsion system has several limitations that should apply to all geostationary orbiting satellites. This paper discusses the operational constraints to consider when developing an indigenous geostationary satellite using a fully electric propulsion, radiation exposure, and control mechanism design due to unit displacement and floating ground-design. A high-voltage control unit for electric drives were analyzed.