Thermal-structural analysis procedure of large mesh reflector for space application

The accuracy of geometrical and surface properties of space antenna reflectors have to meet a set of strict requirements that makes the need of evaluation of thermal deformation influence on reflecting surface shape distortions during development of the new structure. Thermal distortion analysis of large antenna reflectors that operate in orbital environment conditions is cross-disciplinary complex problem. In article the procedure of integrated thermal-structural analysis of large membrane structures is presented. Modern software based on the finite element method is applicable for performing the analysis using this procedure. The goal of this procedure is to predict thermomechanical behavior of the reflector structure under transient on-orbit heating load. Analyzing using this procedure allows tracking the evolution of thermal distortion during orbital flight and getting necessary information on geometrical stability of the reflecting surface form. The initial data for performing the analysis are spacecraft geometric model and orbital data. The procedure considers determination of initial prestressed structure configuration. Thermal and structural analyses performed using two different finite element model based on different components of the spacecraft system. According with the procedure, view factor calculations should be made with the thermal model using Monte Carlo method. Using the procedure presented in the article thermomechanical analysis was performed and form accuracy of the reflecting surface of large reflector as a part of spacecraft on the geostationary Earth orbit was estimated. Thermal-structural analysis considered two different of solar declination: March equinox and December solstice as extreme simulation cases for this orbit. To perform a numerical simulation NX and ANSYS are used. The algorithm of direct temperature translation between the nodes of different models is presented. Using the performed analysis results geometrical properties changes of the disturbed parabolic surface were estimated.