Simulating Buffet Aerodynamics of a Hammerhead Model Using Hybrid RANS-LES CFD Modeling

Hybrid RANS-LES modeling is used to simulate the aerodynamic environments related to transonic buffeting for a hammerhead rocket vehicle. Two hybrid RANS-LES approaches are explored using Loci-CHEM at a single test condition. A grid sensitivity of the two approaches is examined in addition to a brief validation of Loci-CHEM’s LES modeling capabilities. A coarse grid LES simulation is also run to examine the impact of the hybrid modeling approach for grids with larger grid spacings. The CFD mean pressure, and the root-mean square and power spectral density of pressure fluctuations are compared to the experiments of the hammerhead model conducted by Schuster et al. (1). Flowfield visualizations of the CFD results are used to help understand the resolution of the buffet simulations in key areas of the flow.