Dsmc computations of sara reentry capsule exposed to weakly ionized gas flow

In the present investigation, the direct simulation Monte Carlo method is employed to simulate hypersonic rarefied gas flows over the Brazilian reentry satellite. The freestream conditions correspond to those experienced by the capsule at 70 and 65 km altitude. At this altitude and re-entry velocity of 7860 m/s, a high temperature shock is formed promot-ing dissociation and possibly ionisation of the air surrounding the vehicle. The chemical reactions are modelled using the Quantum Kinetic (QK) chemistry model and the results are compared with those obtained for non-reacting gas flows. It is found that the chemical reactions lead to a significant reduction of the shock wave temperature which, consequently, causes a decrease in the maximum pressure values and in the shock wave thickness.