Role of entropic instabilities in laminar-turbulent transition on a blunted flat plate

Abstract

The leading edges of hypersonic vehicles are blunted to mitigate surface heat transfer. A key challenge in their design is the estimation of the laminar-turbulent transition location in the presence of strong, curved shocks. In this study on blunted flat plates, we numerically characterize various aspects of disturbance evolution in the entropy layer. Through controlled forcing, we show that entropy layer disturbances can lead to turbulence without the conventional first and second modes.