Nonequilibrium Flow Around a Blunt Wedge

Abstract

In this study, we investigate Mach 15 hypersonic flow of a five-species air mixture over a 15 deg blunt wedge, accounting for nonequilibrium aerothermodynamic effects. Prior investigations at this flight condition have employed a range of methodologies, including particle-based approaches such as direct molecular simulation (DMS), which serves as a high-fidelity reference to the current study. Here, the same configuration is accessed using both NASA’s Fun3D and the CREATE Kestrel simulation framework, with the kCFD module as the flow solver that recently was extended to the hypersonic regime. Key quantities from both Kestrel and Fun3D produce qualitatively similar results to the DMS. Overall, the results obtained using Kestrel’s nonequilibrium thermochemistry settings exhibit better agreement with many aspects of the DMS than Fun3D, particularly in predicting the shock standoff distance and stagnation point peak heating. These findings provide a guide for using DMS to help validate existing thermochemistry models and provide improved confidence in using Kestrel to predict key nonequilibrium phenomena in high-speed flows.