Aerothermodynamic and Feasibility Study of a Deployable Aerobraking Re-Entry Capsule

A new small recoverable re-entry capsule with deployable heat shield is analyzed. The possible utilization of the capsule is for safe Earth return of science payloads or data from low Earth orbit at an inexpensive cost, taking advantage of its deployable structure to perform an aerobraking re-entry mission, with relatively low heat and mechanical loads. The system concept for the heat shield is based on umbrella-like frameworks and existing ceramic fabrics. An aerothermodynamic analysis is developed to show that the peak heat flux, for a capsule with a ballistic coefficient lower than 10 kg/m super(2), is in the range 250-350 kW/m super(2) and the corresponding surface temperatures are sustainable by off-the-shelf ceramic materials. The article summarizes the main concept and the numerical predictions concerning the re-entry trajectories, the aero-thermal loads, the possibility to control the re-entry trajectory varying the capsule cross-sectional surface. Attention is focused on the effect of the material surface catalyticity on the surface heat flux, in presence of reacting gas mixtures formed behind the strong shock wave in front of the capsule.