Turbulent Inflow Generation for Direct Simulations of Hypersonic Turbulent Boundary Layers and Their Freestream Acoustic Radiation

Direct numerical simulations (DNS) of hypersonic turbulent boundary layers and their freestream acoustic radiation are conducted with a recycling-rescaling (RR) based or a digital-filter (DF) based turbulent inflow generation methodologies. The flow conditions of the simulations falls within the range of nozzle exit conditions of the Purdue Mach 6 Quiet Tunnel. The study provides a first ever comparison between two distinct turbulent inflow generation methodologies at a common hypersonic condition, in terms of both the turbulence statistics within the boundary layer and the acoustic pressure statistics in the free stream. The study shows that simulation results compare well downstream of the adjustment region between the RR- based and the DF-based methodologies