Computation of hypersonic turbulent boundary layers with heat transfer

Abstract

Theme T concept of eddy viscosity has been applied to predict turbulent boundary layers in hypersonic flow regions.' Hopkins et al. found that the multilayer viscosity model underpredicts the skin-friction coefficient by around 10% for hypersonic flow conditions. The neglected density fluctuation terms in the Reynolds stress were identified as the cause of this deficiency. Recent experimental investigations on turbulent boundary layers revealed that the turbulent transport of energy decreases more rapidly toward the wall than the momentum transport. Their results seem to indicate that the heat transfer and temperature profile of turbulent flows cannot be ascertained by an oversimplified constant turbulent Prandtl number. At hypersonic Mach numbers, experimental data also recorded a distinct normal pressure gradient within the turbulent boundary layer. At the present time, no analytical method or systematic evaluation has been attempted to include these phenomena. The present analysis intends to determine the significance of the aforementioned phenomena and also to provide suitable means to improve the numerical prediction scheme for hypersonic turbulent boundary layers.