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arXiv · 0707.3399

Nonlinear analysis of a simple model of temperature evolution in a satellite

Jose Gaite·Angel Sanz-Andrés·Isabel Pérez-Grande
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Abstract

We analyse a simple model of the heat transfer to and from a small satellite orbiting round a solar system planet. Our approach considers the satellite isothermal, with external heat input from the environment and from internal energy dissipation, and output to the environment as black-body radiation. The resulting nonlinear ordinary differential equation for the satellite's temperature is analysed by qualitative, perturbation and numerical methods, which show that the temperature approaches a periodic pattern (attracting limit cycle). This approach can occur in two ways, according to the values of the parameters: (i) a slow decay towards the limit cycle over a time longer than the period, or (ii) a fast decay towards the limit cycle over a time shorter than the period. In the first case, an exactly soluble average equation is valid. We discuss the consequences of our model for the thermal stability of satellites.

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Jose Gaite, Angel Sanz-Andrés, Isabel Pérez-Grande. 2007-07-23. Nonlinear analysis of a simple model of temperature evolution in a satellite. https://doi.org/10.1007/s11071-009-9488-x

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