Prediction of aerothermal characteristics of a generic hypersonic inlet flow

Accurate prediction of aerothermal surface loading is of paramount importance for the design of high-speed flight vehicles. In this work, we consider the numerical solution of hypersonic flow over a double-finned geometry, representative of the inlet of an air-breathing flight vehicle, characterized by three-dimensional intersecting shock-wave/turbulent boundary layer interaction at Mach 8.3. High Reynolds numbers (Re-L approximate to 11.6 x 10(6) based on free-stream conditions) and the presence of cold walls (T-w/T-o approximate to 0.26) leading to large near-wall temperature gradients necessitate the use of wall-modeled large eddy simulation (WMLES) in order tomake calculations computationally tractable. The comparison of the WMLES results with experimental measurements shows good agreement in the time-averaged surface heat flux andwall pressure distributions, and theWMLES predictions show reduced errors with respect to the experimental measurements than prior RANS calculations. The favorable comparisons are obtained using a standard LES wall model based on equilibrium boundary layer approximations despite the presence of numerous non-equilibrium conditions including three-dimensionality in the mean, shock/boundary layer interactions, and flow separation. We demonstrate that the use of semi-local eddy viscosity scaling (in lieu of the commonly used van Driest scaling) in the LES wall model is necessary to accurately predict the surface pressure loading and heat fluxes.

Automated summary

Accurate prediction of aerothermal surface loading is essential for high-speed flight vehicle design. Numerical solution of hypersonic flow over a double-finned geometry with 3D shock-wave/turbulent boundary layer interaction at Mach 8.3 using wall-modeled large eddy simulation (WMLES) shows good agreement with experimental measurements and improves accuracy compared to prior RANS calculations.