Accession Number:

ADA563832

Title:

Numerical Simulation of Transition in Hypersonic Boundary Layers

Descriptive Note:

Final rept. 1 Apr 2008-30 Nov 2010

Corporate Author:

ARIZONA UNIV TUCSON DEPT OF AEROSPACE AND MECHANICAL ENGINEERING

Report Date:

2011-02-01

Pagination or Media Count:

281.0

Abstract:

The laminar-turbulent transition process in supersonic and hypersonic boundary layers was investigated using spatial and temporal Direct Numerical Simulations DNS. Our previous research indicated that oblique breakdown might be a highly relevant nonlinear mechanism for supersonic boundary layers. However, a nonlinear mechanism would only be relevant for the transition process if this mechanism can lead to fully developed turbulence. Hence, to address this question, the late nonlinear transition regime of a supersonic flat-plate boundary layer at Mach 3 was studied using spatial DNS. These simulations demonstrated that a fully turbulent flow can develop via oblique breakdown. We also investigated the nonlinear disturbance development in a hypersonic boundary layer on a sharp circular cone at Mach 8 using spatial and temporal DNS. It was confirmed in these simulations that fundamental resonance and oblique breakdown are the viable paths to transition in hypersonic boundary layers.

Subject Categories:

  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE