Direct Numerical Simulation on the Receptivity, Instability, and Transition of Hypersonic Boundary Layers

TLDR

Accurate prediction of laminar‑to‑turbulent transition in hypersonic boundary layers is crucial because it directly affects aerodynamic heating, drag, and vehicle operation, and recent advances in DNS have uncovered new transition mechanisms. This review surveys recent DNS work on hypersonic boundary‑layer receptivity, instability, and transition, and outlines current status and future research directions. The authors synthesize findings from spatial DNS studies using high‑order shock‑capturing and shock‑fitting finite‑difference methods to elucidate transition mechanisms.

Abstract

The prediction of the laminar-turbulent transition of boundary layers is critically important to the development of hypersonic vehicles because the transition has a first-order impact on aerodynamic heating, drag, and vehicle operation. The success of transition prediction relies on a fundamental understanding of the relevant physical mechanisms. In the 20 years since the review by Kleiser & Zang (1991) on the direct numerical simulation (DNS) of the boundary-layer transition, significant progress has been made on DNS in the hypersonic flow regime and in the spatial DNS approach. Many high-order shock-capturing and shock-fitting finite-difference methods have been developed and extensively applied to numerical simulations of the hypersonic boundary-layer transition. DNS has become a powerful research tool and has led to discoveries of new transition mechanisms. This article reviews the recent progress of DNS on hypersonic boundary-layer receptivity, instability, and transition. The current status and future directions are also presented.