Thermal Analysis and Designing of Spacecraft Payloads and Control System

Abstract

Thermo vacuum testing of satellite payloads are done to study the behavior of payloads under space condition. The aim of the present study is to understand the temperature profile of the panels through simulation software, design the thermal control system and to compare it with the data obtained through thermo vacuum test and further optimize the thermal control system design. A temperature gradient of around 20°C is maintained over the panels to avoid thermal distortion and to achieve this, various instruments are used like PID Controller to control temperature, RTD Sensor to sense the temperature, Infrared (IR) Lamps to provide artificial heating, etc. A basic study of Thermo vacuum test and various instruments used in testing was undertaken. Also thermo vacuum testing was carried out on a black body setup to validate the thermal control system. The temperature was controlled between the set temperature range and a successful testing of the system was conducted. The thermal simulation of South and North Panel of typical satellite was done using simulation software and the temperature distribution over the panels and the subsystems was obtained. There after thermal control system design was done for providing artificial heating to the panels and was implemented in the thermo vacuum testing of the panels and the desired gradient of around 20°C to be maintained over the panel was achieved. The temperature results of test and simulation was compared and the difference obtained was ̴ 2°C. In order to reduce the gradient further, new control system design was checked through simulation and finally two different designs for North and South Panel were finalized which had around 3-4°C lesser gradient than the older design. Hence optimized design solution was obtained which can be implemented in further test to be conducted.