Uncertainty and sensitivity analysis of heat transfer in hypersonic three-dimensional shock waves/turbulent boundary layer interaction flows

Abstract

Hypersonic shock waves/turbulent boundary layer interaction flow can cause severe localized thermal loads, while the fluctuations in freestream conditions and inevitable mechanical vibrations can strongly influence the flow structures and heat transfer. This study aims to quantify the uncertainties in heat transfer and pressure of fin-plate configurations and find their main contributors. Freestream velocity, freestream static pressure, freestream static temperature, wall temperature, and fin angles are chosen as uncertainty sources. The point-collocation non-intrusive polynomial chaos method is employed to propagate the uncertainties. Subsequently, Sobol indices are utilized to denote the contribution of each input parameter. The uncertainty and sensitivity results are plotted along representative lines and on the entire bottom surface to obtain the key parameters of uncertainties. As a consequence, the uncertainty in heat transfer can exceed 30%, which is higher than that in pressure. Freestream velocity, freestream static pressure, and fin angles are the key parameters of heat transfer. Freestream velocity is the biggest contributor to the uncertainty in heat flux near the heat flux peak by influencing flow reattachment. Fin angles dominate the developments of primary vortexes and are the source of the uncertainties near the leading edge of fins. The Sobol index of freestream static pressure is relatively high at the separation line, which reveals that the boundary of flow separation is sensitive to static pressure.