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Table of Content

    25 June 1996, Volume 16 Issue 03 Previous Issue    Next Issue
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    STUDY ON THE TEMPERATURE FIELD OF CPL CAPILLARY WICK EVAPORATOR USING ONE-DIMENSIONAL INVARIABLE TEMPERATURE PHASE CHANGE INTERFACE MODEL
    Qu Wei; Zhang Jiaxun; Liu Jifu (Harbin Institute of Technology, Harbin 150001)
    1996, 16 (03):  . 
    Abstract ( 1908 )   Save
    ne-dimensional invariable temperature phase change interface model on CPL capillary wick evaporator is presented as follows: the temperature of evaporator wall, liquid and vapor only change along the axis direction, there is a vapor-liquid interface with saturation temperature between the wall of evaporator, vapor and liquid, at with heat transfer occurs. Based on this model, the one-dimensional energy conservation equation with a special term of inner heat source is applied to solve the temperature profile. In the calculation, several heat transfer coefficients are evaluated and recommended. Giving the boundary conditions, the temperature field of the evaporator can be obtained numerically. The wall temperature values from numerical calculation have acceptable agreement with that of experimental results.
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    BLOCKING WAVELET TRANSFORM ENCODING FOR SATELLITE REMOTE SENSING IMAGE
    Huang Puming; Ju Dehang; Zhou Quan (Xi'an Institute of Space Radio Engineering, Xi'an 710000)
    1996, 16 (03):  . 
    Abstract ( 1611 )   Save
    This thesis presents a Blocking Wavelet Transform Encoding, which can found a theory basis for satellite remote sensing image compression because of its short store time: Using the self-relativity of each band, we can adopt the improved zerotree encoding for the wavelet coefficients and high compression ratio is obtained.
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    CALCULATION METHOD OF TRANSLUNAR TRAJECTORIES FOR DIRECT STRIKING IN SPECIFIED CONDITIONS
    Yan Hui; Chen Shilu; Lu Xuefu (Northwestern Polytechnical University, Xi'an 710072)
    1996, 16 (03):  . 
    Abstract ( 1717 )   Save
    In this paper, obtained the translunar trajectory for direct striking the moon, which satisfied some constraints including translunar flight time, lunar landing date. incidence angle of lunar landing and parking orbit, through building the mathematical models of translunar trajectory, employing varied tolerance polyhedrons algorithm and penalty functions to search two bourdary values, and using the method of a succession of two-body trajectories to determine the approximative initial values of iteration.
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    SATELLITE COMMUNICATION IN GEOSYNCHRONOUS ORBIT WITH SMALL INCLINATION
    Li Yuheng; Hao Henian (Xi'an Satellite Control Center, Xi'an 710043)
    1996, 16 (03):  . 
    Abstract ( 1849 )   Save
    he operation lifetime of a geosynchronous satellite depends on many factors. In the end of its lifetime, the payloads in the satellite are still working well,but the satellite can't be controlled in north-south direction for fuel shortage in the satllite, it can be controlled enly in west-east direction. If the satellite work in an inclined orbit, could use this satellite for more years and save a lot of money. On the other hand, it also brings about new problems in communication. This paper discusses the problems deeply and gives the calculation results on the condition of different inclinations and the ways to solve the problems.
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    DEVELOPING TREND OF EVA SPACE SUIT GLOVES
    Wei Bin; Yuan Xiugan (Beijing University of Aeronautics and Astronautics, Beijing 100083)
    1996, 16 (03):  . 
    Abstract ( 1776 )   Save
    VA glove is a important part of EVA space suit. The glove must protect the hand from a wide range of hazards including vacuum' radiation. extreme temperature. micro-meteoroids. However, the glove must also allow the astronautics to perform tasks with his or her hands. The above criteria are obviously contradictory. In this paper, the basic function and structure of EVA glove, exsiting problems and developing trend of EVA glove are presented.
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    SAMPLING VERIFICATION PLAN FOR STEADY STATE AVAILABILITY OF SYSTEMS
    Sun Zhuling (Shanghai Jiao Tong University, Shanghai 200030)
    1996, 16 (03):  . 
    Abstract ( 1673 )   Save
    n this paper sampling verification plan of standard form for steady state availability of systems is given when both the operating time and the repair time distributions are free but their variation coefficients are known.
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    PASSIVE LEAK DETECTION TECHNIQUE FOR SPACE VEHICLE
    Kang Xiaolu (Lanzhou Institute of Physics, Lanzhou 730000)
    1996, 16 (03):  . 
    Abstract ( 1604 )   Save
    In this paper, the concept of passive leak detection technique for space vehicle was proposed. The survey of its needs, development and some gas analysis methods were given. Some techniques that may be used in passive leak detection for space vehicle were shown. Finally, the key technologies of passive leak detection for space vehicle were studied.
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    CALCULATING RADIATION EXCHANGE FACTORS OF RADIANT COOLER BY USING MONTE CARLO METHOD
    Gao Chunhua; Yao Hai (Xi'an Jiaotong University, Xi'an 710049)
    1996, 16 (03):  . 
    Abstract ( 1689 )   Save
    Radiant heat transfer in real enclosure with diffuse emission and specular reflection surfaces has been studied by the Monte Carlo method. Radiation exchange factors of radiant cooler have been calculated by Monte Carlo method. The flow chart of computer program is described and the calculated results are discussed.
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    APPLICATION OF IEEE 488 BUS IN CHARACTERISTIC TEST OF MOMENT WHEEL
    Dong Lei; Yu Min (Beijing Institute of Environment Test (Beijing Institute of Computer Application &Engineering, Beijing 100029) Simulation Technology, Beijing 100084)Dong Tao (Beijing Institute of Control Engineering, Beijing 100080)
    1996, 16 (03):  . 
    Abstract ( 1902 )   Save
    In this paper, the general structure and open-loop test principles of Moment wheel are briefly described. Then, the open-loop moment wheel characteristic test system founded on IEEE 488 Bus is comprehensively introduced. The constitution of the automatic test system, test items, test process and test results are also explained. By these, the populavizable value of this test system in satellite manufacturing are pointed out.
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    STRENGTH PROPERTIES OF WINDOW GLASS OF MANNED SPACECRAFT
    Song Lixin; Hu Xingfang (Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050)Wu Guoting (Beijing Institute of Spacecraft System Engineering, Beijing 100086)
    1996, 16 (03):  . 
    Abstract ( 2027 )   Save
    The strength behaviours of the window glass of spacecraft were discussed based on the strength theories in this paper. It is pointed out that the strength design for the window glass must be based on the fracture mechanics, not just the data of the tensile strength or bending strength measured on small samples Because the cracks existing on glass surface will greatly influence the strength of the window glass, they must be controlled and inspected carefully, so as to ensure the strength of window glass to meet the requirements of application. Considering the subcritical growth of the cracks in glass, the window glass should not be loaded in atmosphere before its servies. In the structural design of the windows, it should be noted that the surfaces in high tensile stress should not contact with moisture.
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    DEVELOPMENT OF A REAL-TIME SIGNAL SOURCE FOR INFRARED EARTH SENSOR
    Lu Mingyu (Tsinghua University, Beijing 100084)Yi Kui; Yang Junfa; Deng Ruzhen (Beijing Institute of Control Engineering, Beijing 100080)
    1996, 16 (03):  . 
    Abstract ( 1832 )   Save
    he principle and configuration of a signal source of oscillatorilly scanning infared earth sensor for geostationary satellite are given, and the method of software development is presented. Through simplification and improvement of the computation process, the software makes full use of the hardware resource, especially the 8031 microprocessor. The performance of the signal source is enhanced, and the requirement for the signal source's real-time operation is reached.
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