Hypersonic turbulent flow simulation of FIRE II Reentry vehicle afterbody

This paper presents a numerical investigation of the hypersonic reacting How around the FIRE II reentry capsule. At the chosen freestream conditions, the forebody boundary layer and the separated flow on the afterbody are turbulent. The Reynolds-averaged Navier-Stokes method along with two commonly used turbulence models are used to compute the flowfield. Accurate prediction of turbulent separated flow at hypersonic conditions is challenging due to the limitations of the underlying turbulence models. The presence of turbulent eddy viscosity in the flow simulation results in a smaller separation bubble than the laminar solution at identical conditions. Also, the two turbulence models predict different levels of eddy viscosity in the neck region. This has a dominant effect on the separation bubble size and the surface pressure. On the other hand, the eddy viscosity values in the near-wall region determine the heat transfer rate to the body. The two models predict comparable heating rates on the conical frustum, and the results match in-flight measurement well. By comparison, surface pressure predictions are appreciably higher than the data