Aerothermodynamics Behind a Blunt Body at Superorbital Speeds

Abstract

Results of an experimental, numerical, and analytical study of the hypersonic laminar near-wake flow of a 45° half-angle blunted cone are presented. A superorbital expansion tube facility, which can generate different planetary atmospheric compositions, was used for the experiments. In the present instance, two test gases [air and a mixture of 96%CO 2 -4%N 2 (simulating the Martian atmosphere)] were used. Superorbital speeds above 8 km/s were generated at specific enthalpies of 44.5 MJ/kg (air) and 32.9 MJ / kg (96 % CO 2 -4%N 2 ). Measurements consisted of surface pressure and heat flux, and both showed good agreement with theoretical and numerical predictions. It was also noted that, based on numerical data, chemical reactions seemed to be stronger in the case of the test gas simulating the Martian atmospheric composition when compared with those of air.