Aerodynamic drag estimation of ultra-low orbit spacecraft

Abstract

The ultra-low orbit spacecraft has the advantages of high resolution, easy de-orbit and low launch cost. Although that atmospheric density at this height is only 10–11 to 10-9kg/m3, the aerodynamic drag acting on the satellite can be millinewton or even Newton, which is the main reason for the fall of the ultra-low orbit spacecraft. In this paper, the method of aerodynamic drag estimation for the ultra-low orbit spacecraft is given, and the influence factors of aerodynamic drag are analysed, the calculation formula of drag coefficient is emphatically derived, and the influence factors of drag coefficient are studied. The drag coefficients under the conditions of typical orbit and space environment are given. In order to reduce the drag, the SLO spacecraft should be designed as a slender body configuration, and at this time, the drag effect brought by the side cannot be ignored, which should be paid more attention to in the overall configuration and layout design of the spacecraft.