Aerodynamic Analysis and Drag-reduction Design for Ultra-low-orbit Satellite

Abstract When the satellite is operating at an orbital height of 120-300km, aerodynamic drag becomes the most important factor affecting ultra-low orbital attenuation and attitude disturbance. Based on the theory of free-molecular flow, the model of aerodynamic drag of a panel in free-molecular flow is established firstly, and then the influence of the angle of attack, adaptation coefficient, and the molecular velocity ratio on the drag coefficient of the panel is analysed. Finally, A reduced drag design method for a ultra-low-orbit satellite is proposed based on the analysis results. And it is validated by the simulation results. The approaches presented in this paper can be applied to aerodynamic design and calculation of ultra-low-orbit satellites.