Reliable prediction of hypersonic boundary-layer transition

Determine reliably the onset of turbulence in hypersonic boundary layers to support accurate prediction of aerodynamic and aerothermal loads on high-speed vehicles.

Background

The paper identifies transition prediction as a fundamental unresolved issue in high-speed vehicle design. Whether a hypersonic boundary layer remains laminar or becomes turbulent strongly affects skin friction, wall heating, structural margins, thermal-protection requirements, and payload capability. Existing uncertainty in predicting transition can therefore lead either to overly conservative designs or to underestimated thermal loads.

The study addresses only part of this broader problem by analyzing axisymmetric global modes and transient disturbance growth over a high-enthalpy Martian-entry capsule. Its results identify shear–entropy-layer transient growth as a plausible linear amplification pathway, but they do not establish a complete or reliable criterion for the actual onset of turbulence.