Thermal Design of a Microsatellite in Sun-Synchronous Orbit Based on Bayesian Optimization

The thermal control subsystem is one of the critical subsystems of a satellite. Optimization of the design of this subsystem could benefit a satellite’s power and mass budgets. In previous optimization studies regarding the thermal management of low Earth orbit satellites, solstices are typically assumed to be the thermally extreme cases. However, this could not always be accurate. In addition, previous studies often evaluated specific parts of the thermal system, while overlooking the dynamics of energy conversion within the satellite. In this study, thermally extreme cases are identified using a lumped analysis approach. Moreover, heat dissipation of certain components is modeled based on the relationship between the generation and the consumption of power. The process begins with an orbital analysis, which provides inputs for the lumped analysis. According to the results of the lumped analysis, finite element analyses are performed for the worst hot and the worst cold cases. The aim is to minimize the need for heater energy consumption by adjusting the coordinates of the corners of the radiators, where constraints are set by the safe temperature intervals of specific components. This computationally demanding optimization problem is solved by Bayesian optimization, also a first for a satellite design study. The optimized system requires a reduced amount of heater energy while satisfying the temperature constraints.