Analysis of Entry Vehicle Aerothermodynamics Using the Direct Simulation Monte Carlo Method

This paper presents simulations of the aerothermodynamics of the Apollo Command Module under rarefied conditions with the direct simulation Monte Carlo method. Relevant details of the application setup and simulation performance are presented. Threedimensional windtunnel model and flight simulations are made. For the windtunnel model simulations, the direct simulation Monte Carlo method and an analytical free molecular flow method are compared with existing windtunnel data. These simulations are made at different angles-of-attack and Reynolds numbers. The Monte Carlo simulations provide accurate lift and drag results for the windtunnel test. The pitching moment is sensitive to changes in Reynolds number and in center-of-gravity location. Reasonable heat transfer simulation results are obtained. For the flight simulations, the pressure results are reasonable in comparison with the Newtonian theory. The corresponding heat transfer simulation results are reasonable in comparison to available heat transfer empirical data.