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


Personal Author(s) : Fasel, Hermann F ; Gross, Andreas ; Koevary, Clayton ; Laible, Andreas ; Mayer, Christina ; Sivasubramanian, Jayahar


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a563832.pdf


Report Date : Feb 2011


Pagination or Media Count : 281


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.


Descriptors :   *BOUNDARY LAYER , HYPERSONIC FLOW , MATHEMATICAL MODELS , NONLINEAR SYSTEMS , SUPERSONIC FLOW , TURBULENT FLOW


Subject Categories : Fluid Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE