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    25 December 1997, Volume 17 Issue 06 Previous Issue    Next Issue
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    PREDICTION OF EQUILIBRIUM TEMPERATURE IN SPACECRAFT THERMAL BALANCE TESTING
    Weng Jianhua(Tongji University,Shanghai 200092)Pan Zengfu(Beijing Institute of Spacecraft System Engineering,Beijing 100086)Min Guirong(Chinese Academy of Space Technology,Beijing 100081))
    1997, 17 (06):  . 
    Abstract ( 1547 )   Save
    Nonlinear regression based on Least square method is used to predict the equilibrium temperature with experimental data,The results are in accordance with the analysis that the measured temperature will exponentially vary with time from a certain moment after the beginning of the experiment.case,and the equilibrium teperature can be predicted efficiently by the method.The choosing of regression data is important to the reasonableness of the predicted equilibrium temperature,while choosing of the initial value of the regression parameters will not affect the results when they are convergent.
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    EXPERIMENTAL INVESTIGATION ON FLUCTUANT PHENOMENON OF FLUID CIRCULATION IN TWO-PHASE CAPILLARY PUMPED LOOPS
    Wang Jinliang,Ma Tongze,Zhang Zhengfang(Institute of Engineering Thermophysics,CAS,Beijing 100080)Hou Zengqi(Beijing Institute of Spacecraft System Engineering,Beijing 100086))
    1997, 17 (06):  . 
    Abstract ( 1700 )   Save
    The fluctuant phenomenon of fluid circulation appears in the starting and working processes of two-phase capillary pumped loops(CPL).This problem was preliminarily studied by experiment.The origins of the fluctuant phenomenon were analyzed and the fluctuant situations of pressures and temperatures in the inverted type evaporator were investigated.The variation regularity of the output pressure in the evaporator in different conditions were obtained.
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    STABILITY ANALYSIS OF JET-CONTROLLED SYSTEM FOR FLEXIBLE LIQUID-FILLED SPACECRAFT
    She Haiying Qu Guangji Li Zhi(Beijing Institute of Spacecraft System Engineering,Beijing 100086)Geng Yunhai Yang Di(Harbin Institute of Technology,Harbin 150001))
    1997, 17 (06):  . 
    Abstract ( 1629 )   Save
    The paper presents the stability analysis of pseudorate jet-controlled attitude system for spacecraft with large flexible solar arrays and liquid-filled tanks.A dynamic model including highly underdamped flexible and sloshing modes is used for system design.The dynamic characteristics of the modulator are discussed in detail,and the describing function is derived.Analysis approach is reviewed.Nonlinear stability analysis is performed using the describing function analysis of the modulator on a Nichols plot.
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    ANALYSIS OF HUMAN OPERATION ANTILAPSE DESIGN IN MANNED VEHICLE
    Zhou Qianxiang Long Shengzhao(Institute of Space MedicoEngineering,Beijing 100094))
    1997, 17 (06):  . 
    Abstract ( 1495 )   Save
    Any human operation error will result in failure of manned vehicle and danger to astronaut's life.In this paper,the characters of human operation in vehicle system are described,and the problem of design antilapse also discussed,on the basis of which the antilapse design method is put forward. 
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    EFFECTS OF EVA SPACE GLOVE ON MANUAL PERFORMANCE AND RESOLUTION METHOD
    Pang Cheng Chen Jingshan(Institute of Space MedicoEngineering,Beijing 100094))
    1997, 17 (06):  . 
    Abstract ( 1539 )   Save
    Astronaut′s hand capabilities such as dexterity and tactile perception are major factors in man′s superiority over automatic or robotic devices for EVA tasks.This paper discussed the principal effects of space glove on manual performance in detail and gave some medicoengineering considerations for resolving the contradiction between protective function of space glove and maintenance of basic hand performance.
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    ANALYSIS OF SEAL FAILURE IN SPACE ENVIRONMENT
    Wu Guoting(Beijing Institute of Spacecraft System Engineering,Beijing 100086))
    1997, 17 (06):  . 
    Abstract ( 1668 )   Save
    The failure in space environment of seal materials used in manned spacecraft has been analysed.Such effects as fragility increase of the sealant in low temperature and the surface of seal material in high temperature,permeability increase of seal material in vacuum environment and elasticity loss due to radiation are the main cause of failure in space environment.The contamination of the surface such as window glass from condensable material out of seal material in vacuum environment is another important phenomenon which must be considered in seal design.
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    DISCUSS ON FORMULA OF DOPPLER FREQUENCY TO VELOCITY
    Wu Yi Zhu Jubo Yi Dongyun Wang Zhengming(National University of Defense Technology,Changsha 410073))
    1997, 17 (06):  . 
    Abstract ( 2353 )   Save
    This paper points out that the current formula of Doppler frequency to velocity has bigger error in the case of high precision trajectory,and gives a new transfer formula.Satisfactory results have been obtained through the use of this new formula to actual measured data processing.
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    ANALYSIS OF REENTRY VEHICLE IMPACT ERROR RESULTING FROM ROLL VELOCITY CHANGES
    Yang Huiyao(The Second Artillery Engineering College,Xi′an 710025))
    1997, 17 (06):  . 
    Abstract ( 1590 )   Save
    This paper researches into reentry vehicle impact errors which result from the roll velocity changes by use of rotor dynamic theory.The roll regularity and balance attackangle are presented through analysis of general attackangle equation,and the impact dispersion of nonspinning vehicle is got.Steady roll impact error can be obtained when the reentry trajectory is divided into many sections.Rollpasszero(RPZ) impact error is analyzed and calculated on the basis of RPZ height.The roll resonance phenomena are discussed.The conditions of roll resonance and dispersion calculation formula are given also.Finally,Several important conclusions are presented.
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    IMPINGEMENT FORCES OF ATMOSPHERIC MOLECULES TO A FREEFLYING PLANE WAKE SHIELD FACILITY IN LOWEARTH ORBIT
    Zhang Hualin Da Daoan(Lanzhou Institute of Physics,Lanzhou 730000))
    1997, 17 (06):  . 
    Abstract ( 1608 )   Save
    The impingement forces of atmospheric molecules to a freeflying plane wake shield facility(PWSF)in 300km lowearth orbit is investigated.Atmospheric gases are assumed Maxwellian gases.In our computation,the elastic and the complete inelastic collisions between atmospheric molecules and PWSF surfaccs are adopted to determine the impingement interactions.So,the real impingements are situated between the two interactions.Our results show that,for a 5m diameter PWSF in 300km orbit,the impingement force of the atomic oxygen(O) out of 6 main gas species is the greatest one,and the impingement force of argon(Ar)is the smallest one which is 4 orders of magnitude less than O's.The total force produced by the atmospheric molecules is less than 0082N
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    PERFORMANCE COMPARISON OF TWO MOUNTING CONFIGURATIONS OF INFRARED EARTH SENSORS
    Li Jie(Beijing Institute of Control Engineering,Beijing 100080))
    1997, 17 (06):  . 
    Abstract ( 1499 )   Save
    In this paper,the algorithms of attitude determination and the performance of two mounting configurations of infrared earth sensors are compared.In the first configuration two sensors are mounted vertically,and in the second one they are mounted oppositely.The results of the study show that the configuration of two oppositely mounted infrared earth sensors improves the performance of satellite attitude determination.
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