Computational Modeling of the Curing of a Frame of an Inflatable Satellite Antenna in Near-Earth Orbit

Temperature analysis of a new technological process, curing of prepregs in near-Earth orbit, is performed via computational modeling. The problem arose with the currently discussed possibility of using inflatable antennas for small space satellites. Inflatable antennas have a number of advantages over classic extendable metal antennas. However, in order to ensure continuous operation of inflatable antennas, it is necessary that they acquire rigidity over time and stop depending on the air pressure in them. This can be achieved by using a solid frame made of an orbital-curable prepreg. Placement of special equipment for heating prepregs in the satellite body is undesirable, because it increases weight and dimensions of a satellite. The authors propose heating structural elements in space by radiation emitted from the Sun and the Earth. This novel idea requires justification and verification by means of field experiments and computational modeling. In this work only one of the aspects (the temperature effect) of the in-orbit curing technological process is analyzed using the results of numerical experiments. The peculiarity of the thermal boundary value problem is in boundary conditions where the heating of the frame of inflatable antenna by the Sun's radiation flux and its cooling as a result of heat radiation of the structure itself in space are taken into account. It is established that, to achieve the required temperatures, instead of a simple prepreg frame, the prepreg with a thin layer of copper coating is to be applied. The features of the temperature distributions in the structure in the course of its rotation are revealed. The time intervals are determined at which the antenna orientation with respect to the solar flux should be changed to obtain the temperatures to cure all elements of the frame in the course of a small number of revolutions around the Earth, that is, as long as a high gas pressure preserves in the inflatable antenna.