Aerothermal Analysis and Design of HyperSat: An Aerobraking CubeSat With a Mechanically Deployable Heatshield

Low-cost hypersonic platforms have been suggested as a solution to the growing need for hypersonic test data given the limitations of existing ground test techniques. As a part of these efforts, Georgia Tech and the Georgia Tech Research Institute have been developing a low-cost Hypersonic 12U CubeSat platform (HyperSat) to be used as a hypersonic testbed. HyperSat begins in a GTO orbit and uses aerobraking passes to expose the vehicle to hypersonic conditions. In order to fit within a 12U footprint and survive atmospheric heating, HyperSat utilizes a mechanically deployable heatshield with a flexible thermal protection system (FTPS). This work describes the trajectory, aerothermal analysis, and subsequent geometry modifications to ensure that the FTPS remains within heat flux material limits. The expected entry environments were bounded using a Monte Carlo trajectory simulation varying aerodynamic properties, entry conditions, atmospheric properties, and mass properties. These bounds were then utilized to perform high-fidelity aerothermal CFD simulations using LAURA and FUN3D to predict heating on the FTPS. Localized hot spots were identified at the interfaces between the deployable panels, motivating design modifications, including changes to the cone angle and nose thickness, to minimize heating.