Dynamic Simulations of Atmospheric-Entry Capsules

摘要

Viscous free-oscillation simulations with the OVERFLOW solver are used to predict the aerodynamic behavior of nonlifting capsule shapes in the supersonic-speed regime. Computations using hybrid Reynolds-averaged Navier-Stokes turbulence models are examined for two novel atmospheric-entry capsule configurations: an idealized inflatable decelerator concept and the Orion crew module. The simulation results are validated against nonlinear aerodynamic models determined from free-flight ballistic-range data analysis. For the Orion crew module, two separate methods of reducing identical range data, along with common models tested in separate range facilities, are included. The computations demonstrate the efficiency and accuracy of dynamic simulations for developing a nonlinear aerodynamic performance database. Analysis indicates that the typical nonlinear bluff-body behavior is characterized by a rate-dependent dynamic response, which is not currently accounted for in common aerodynamic models.