HIGH-ALTITUDE CAPSULE AERODYNAMICS WITH REAL-GAS EFFECTS

Re-entry capsule aerodynamics within a wide range of angles of attack and flight altitudes are examined by the direct simulation Monte Carlo method. The local bridging method is verified by comparison with resu lts of simulations. Capsule stability is analyzed for flight altitudes from 130 km down to 85 ion. Comparison between computed and free flig ht data shows a good agreement. A qualitative change of heat transfer coefficient behavior for different angles of attack during the descent is revealed. The influence of chemical reactions on aerodynamics and flow fields at 85 km is shown to be significant. For a flow simulation in the near-continuum regime, a parallel version of tile direct simul ation code, with static and dynamic load balancing techniques,is used, An efficiency of about 80% is obtained for 256 processors using dynam ic load balancing.