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    25 June 1997, Volume 17 Issue 03 Previous Issue    Next Issue
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    TWO DIMENSIONAL MODELLING AND EXPERIMENTAL VERIFICATION FOR INNER FLOW AND HEAT TRANSFER OF HEAT PIPES
    Li Jindong Li Tinghan (Beijing Institute of Spacecraft System Engineering,Beijing 100086)
    1997, 17 (03):  . 
    Abstract ( 1551 )   Save
    A modelling analysis is presented for the inner flow and heat transfer problem of heat pipes,and a joint two dimensional axial symmetrial flow and heat transfer model is established.Based on it,a numerical simulation is conducted.Compared to the existing experimental results in the same conditions,the deviations of the numerical results from the experimental are small,and their varying regulations are very consistent,too.
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    ATTITUDE CONTROL SYSTEM OF FY 1B SATELLITE
    Xu Fuxiang (Chinese Academy of Space Technology,Beijing 100081)
    1997, 17 (03):  . 
    Abstract ( 1614 )   Save
    The three axis stabilized Earth oriented attitude control system adopted by FY 1 meteorological satellites represents an active control concept.Two satellites have been launched,namely FY 1A and FY 1B.Based on FY 1A's main attitude control system and with the addition of a set of backup system,FY 1B has taken a series of redundancy measures and designed an all directional attitude reacquisition method as failure countermeasures.The system's design has proved to be perfect and successful via flight test and on orbit trouble emergency removing.The maiden use of reaction wheel control,bias momentum control,magnetic nutation precession,wheel unloading control,and all directional attitude reacquisition has achieved fairly good results,thus accumulating valuable experiences for the design of long life satellite attitude control systems.
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    DESIGN OF MULTI TASK REAL TIME OPERATING SYSTEM IN ON BOARD DATA HANDING
    Luo Xanwu (Beijing Institute of Spacecraft System Engineering,Beijing 100086)
    1997, 17 (03):  . 
    Abstract ( 1592 )   Save
    RT86,a real time multi task operating system,is developed for the on board data handling system in accordance with ESA software engineering standards.Its hardware environment is 2 cool redundant Main Control Units(MCU)and several Remote Terminal Units(RTU)which are connected via a 1553B Serial Data Bus(SDB).The system performs telemetry,telecommand and various data management.This paper presents the main points in designing RT86 and the advantage of RT86 in the software organization,development,modification and maintenance.
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    THE STUDY OF FLEXIBLE ANTENNA POINTING CONTROL IN MOMENTUM BIAS SYSTEM
    Qi Chunzi Lü Zhenduo (Beijing Institute of Control Engineering,Beijing 100080)
    1997, 17 (03):  . 
    Abstract ( 1681 )   Save
    From engineering practice,the paper discusses the flexible antenna pointing control problem in momentum bias system which is widely used.The flexible antenna has large size(diameter from 3m to 5m)and requires high pointing precision(0 05°).After deriving the dynamic equations of the satellite with flexible antenna,and analyzing and improving the study of restraining the vibration caused by the movement of flexible antenna,the paper gives a practical method of antenna pointing control in a three axis stabilized satellite with momentum bias system.Finally,after a close loop digital simulation,the paper summarizes the main factors affecting antenna pointing precision.
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    NEW PROGRESS OF DIAMOND FILMS IN AEROSPACE APPLICATION
    Sun Yining,Guo Wantu,Li Jingqi,Liang Xinan (Lanzhou Institute of Physics,Lanzhou 730000)
    1997, 17 (03):  . 
    Abstract ( 1796 )   Save
    The aerospace applications of diamond films in space optics,friction and lubrication ,thermal management of space devices and radiation detection are summarized.The importance of diamond film in aerospace industry and the influence on each others are indicated.The bright prospect of the applications of diamond film in aerospace is expected in near future.
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    MULTI-MISSION GRAVITY GRADIENT AND MAGNETIC STABILIZATION FOR SMALL SATELLITE PLATFORM
    Lin Laixing (Beijing Institute of Control Engineering,Beijing 100080)
    1997, 17 (03):  . 
    Abstract ( 1601 )   Save
    In this paper,the remarkable advantages of Gravity Gradient Small Satellites are first described,such as simple structure,high reliability,low cost,short development time and light weight.Then some technical performances of gravity gradient satellite platform are presented.Finally four models of threeaxis attitude stabilization for small satellite platform are studied.
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    THE MAIN PERFORMANCES AND TEST METHOD OF THE LINEAR CHARGE COUPLED DEVICE
    Ye Peijian (Chinese Academy of Space Technology,Beijing 100081) Liu Fuan (Xi'an Institute of Space Radio Technology,Xi'an 710000) Cao Haiyi (Beijing Institute of Spacecraft System Engineering,Beijing 100086)
    1997, 17 (03):  . 
    Abstract ( 1931 )   Save
    It is very important for the experts working in remote sensor of satellite to know the main performances of the linear Chargecoupledevice.So in this article summarize the performances and the definition of the linear CCD used in satellite,the test methods,the test equipments and the formula to calculate the performance.
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    DISCUSSION ON ARCHITECTURE OF ONBOARD DATA SYSTEM
    Tan Weichi Xing Guiliang (Beijing Institute of Spacecraft System Engineering,Beijing 100086)
    1997, 17 (03):  . 
    Abstract ( 1753 )   Save
    nboard data system sets up the unified data management and supports the system level reconfigurations by networking all the onboard computers.The criteria for selecting the architecture of onboard data system is presented in this paper.Main architectures for parallel computer systems are briefly compared.This paper concludes that several architectures,such as mesh network and crossbar network,are better than the current single bus architecture widely used.
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    AN ENGINEERING METHOD FOR TWO DIMENSIONAL TURBULENT TRAIL OF HYPERSONIC REENTRY BODIES
    Liu Qingyun Zhang Ping (Beijing Institute of Technology,Beijing 100081)
    1997, 17 (03):  . 
    Abstract ( 1758 )   Save
    An engineering model for hypersonic reentry body trail is established in this paper,and a calculation is performed by using boundary layer theory.Prandtl's mixture length theory of turbulent shearing stress and Taylor's eddy exchange theory are used to predict the distribution of velocity and temperature respectively.Lykoudis's method is used to calculate the parameters at the axis of the trail.Also the trail length and free electron number density of the trail are predicted.The results are in agreement with those of the relative references.The purpose of this paper is to give those parameters required for the computation of the radar diffusion section of the trail.
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    A NEW TECHNIQUE TO COMPENSATE FOR ERROR IN SAR ANTENNA POWER RATTERN
    Wang Wutu (Xi'an Institute of Space Radio Technology,Xi'an 710000) Qi Yihong John Litva (Communications Research Lab,McMaster University,Canada)
    1997, 17 (03):  . 
    Abstract ( 1587 )   Save
    A Cost effective,phase only adjustment technique to compensate for any error in SAR antenna power pattern is first presented,secondly,the particular "slowly varying systematic distortions"of SAR antenna subjected to thermal loads are discussed,and then some examples are taken to test the validity of the compensation technique,finally,some important conclusions are given in this paper.
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