Numerical Simulation of Surface Roughness Effects on Receptivity of Hypersonic Flow Over Blunt Cones

The accurate prediction of laminar-turbulent transition in hypersonic boundary layers is a critical part of the aerodynamic heating analyses on hypersonic vehicles. Despite decades of extensive research, the prediction of hypersonic boundary-layer transition is still mostly based on empirical correlation methods or the semi-empirical n e method because a number of physical mechanisms leading to transition are currently not well understood. The receptivity phenomenon, which is the process of environmental disturbances initially entering the boundary layers and generating disturbance waves, is one of these important, but less understood, mechanisms.