[home] [Personal Program] [Help]
tag
11:45
15 mins
Statistics of the subgrid scales after the shock-turbulence interaction
Daniel Livescu, Zhaorui Li
Session: Reacting and compressible flows 2
Session starts: Thursday 27 August, 10:30
Presentation starts: 11:45
Room: Room F


Daniel Livescu (Los Alamos National Laboratory)
Zhaorui Li (Los Alamos National Laboratory)


Abstract:
The interaction of a normal shock with isotropic turbulence (IT) represents a basic problem for studying some of the phenomena associated with high speed flows, such as hypersonic flight, supersonic combustion and Inertial Confinement Fusion (ICF). In general, in practical applications, the shock width is much smaller than the turbulence scales and the upstream turbulent Mach number is modest. In this case, recent high resolution shock-resolved Direct Numerical Simulations (DNS) (Ryu and Livescu, J. Fluid Mech., 756, R1, 2014) show that the interaction can be described by the Linear Interaction Approximation (LIA). By using LIA to alleviate the need to solve the shock, DNS post-shock data can be generated at much higher Reynolds numbers than previously possible. Here, such results with Taylor Reynolds number around $180$ are used to investigate the properties of the subgrid scales (SGS). In particular, it is shown that the shock interaction decreases the asymmetry of the SGS dissipation PDF as the shock Mach number increases, with a significant enhancement in size of the regions and magnitude of backscatter.