A simple model of the hypersonic boundary layer

Abstract

A simple model of the hypersonic boundary layer is proposed. There are three assumptions: The mean velocity profile is linear, the total enthalpy is uniform, and turbulent transport is controlled by sonic eddies, whose rotational Mach number is unity. The model predicts that turbulent transport is slowest at the outer edge of the layer, consistent with the formal assumption of a linear velocity profile. The concentration profile of any conserved scalar is uniform across the boundary layer, matching the boundary condition at the wall. Any difference with the free stream concentration is accommodated by a jump at the outer edge of the layer.