Thermal radiation analysis for small satellites with single-node model using techniques of equivalent linearization

• Linearization criteria are presented for a single-node model of satellite thermal.
• A nonlinear algebraic system for linearization coefficients is obtained.
• The temperature evolutions obtained from different methods are explored.
• The temperature mean and amplitudes versus the heat capacity are discussed.
• The dual criterion approach yields smaller errors than other approximate methods.

In this paper, the method of equivalent linearization is extended to the thermal analysis of satellite using both conventional and dual criteria of linearization. These criteria are applied to a differential nonlinear equation of single-node model of the heat transfer of a small satellite in the Low Earth Orbit. A system of nonlinear algebraic equations for linearization coefficients is obtained in the closed form and then solved by the iteration method. The temperature evolution, average values and amplitudes versus the heat capacity obtained by various approaches including Runge–Kutta algorithm, conventional and dual criteria of equivalent linearization, and Grande's approach are compared together. Numerical results reveal that temperature responses obtained from the method of linearization and Grande's approach are quite close to those obtained from the Runge–Kutta method. The dual criterion yields smaller errors than those of the remaining methods when the nonlinearity of the system increases, namely, when the heat capacity varies in the range [1.0, 3.0] × 104 J K−1.