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The numerical simulation of turbulent hypersonic flows poses a number of significant challenges. Chief among these challenges is the stringent grid resolution requirement in the boundary layer to accurately predict wall heat flux and skin friction. An enabling modeling concept for such flows is the use of wall models to reduce the near wall computational burden. In this paper, we present the development and validation of a turbulence wall model applicable to high Reynolds number flows. We review modeling choices that arise given a use case of cold-wall hypersonic flow with shock-turbulent boundary layer interaction. Finally, we assess the performance of the model in an a posteriori analysis of a hollow cylinder-flare forebody and a large cone-flare forebody, and comment on model performance and limitations.

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In recent experiments performed at the University of Illinois, nitrogen and air flows over a double wedge geometry at Mach numbers varying from 4-7 and stagnation enthalpies varying from 2.1-8.0 MJ/kg were investigated. Selected cases from these experiments are simulated using US3D to ascertain the ability of state-of-the-art finite-volume hypersonic flow solvers to replicate experimental results. Two-dimensional simulations predict an unsteady separation and shock-shock interaction under both reacting and non-reacting conditions. The numerical solutions reach a time-periodic solution for certain experimental conditions. Good agreement is observed between experiment and two-dimensional simulations of the Mach 7 flow conditions when the simulations are limited to the experimental run-time. When run to a large number of flowtimes, the agreement is poor. Three-dimensional simulations of these free-stream conditions show non-uniformities in the wedge boundary layer during flow development.