Shape Optimization of Very-Low-Earth-Orbit Satellites for Drag Reduction

Operating satellites in the very-low-Earth-orbit (VLEO) region has a number of advantages. However, a primary challenge to the sustained operation of VLEO satellites is the significant atmospheric drag resulting from the higher ambient density, which leads to rapid orbital decay and eventual reentry. Therefore, reducing aerodynamic drag is essential for extending the operational lifetime of VLEO satellites. At the same time, it is important to consider the internal volume to ensure that the satellite maintains its functional capabilities. This work presents a shape optimization framework for VLEO satellites aimed at minimizing the aerodynamic drag without compromising the internal volume. The optimization is performed using a genetic algorithm, with drag force calculated via the panel method and validated by the direct simulation Monte Carlo simulations. Under a fixed-volume constraint, the optimal satellite geometry achieves a maximum drag reduction of 60.3% compared to the reference satellite. Furthermore, this study employs multi-objective optimization to simultaneously minimize aerodynamic drag and maximize internal volume. The results demonstrate that the notable improvements in both drag and volume can be simultaneously achieved through shape optimization. Compared to the reference satellite, the optimal satellite geometry offers a drag reduction of 53.9% and a volume increase of 7.6%.