Single-interface Richtmyer-Meshkov turbulent mixing at the Los Alamos Vertical Shock Tube

Journal Article · Tue Apr 12 00:00:00 EDT 2016 · Journal of Fluids Engineering

DOI:https://doi.org/10.1115/1.4032529· OSTI ID:1329860

Wilson, Brandon Merrill ^[1]; Mejia Alvarez, Ricardo ^[1]; Prestridge, Katherine Philomena ^[1]

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1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

We studied Mach number and initial conditions effects on Richtmyer–Meshkov (RM) mixing by the vertical shock tube (VST) at Los Alamos National Laboratory (LANL). At the VST, a perturbed stable light-to-heavy (air–SF₆, A=0.64) interface is impulsively accelerated with a shock wave to induce RM mixing. We investigate changes to both large and small scales of mixing caused by changing the incident Mach number (Ma=1.3 and 1.45) and the three-dimensional (3D) perturbations on the interface. Simultaneous density (quantitative planar laser-induced fluorescence (PLIF)) and velocity (particle image velocimetry (PIV)) measurements are used to characterize preshock initial conditions and the dynamic shocked interface. Initial conditions and fluid properties are characterized before shock. Using two types of dynamic measurements, time series (N=5 realizations at ten locations) and statistics (N=100 realizations at a single location) of the density and velocity fields, we calculate several mixing quantities. Mix width, density-specific volume correlations, density–vorticity correlations, vorticity, enstrophy, strain, and instantaneous dissipation rate are examined at one downstream location. Results indicate that large-scale mixing, such as the mix width, is strongly dependent on Mach number, whereas small scales are strongly influenced by initial conditions. Lastly, the enstrophy and strain show focused mixing activity in the spike regions.

• Research Organization: Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE
• Grant/Contract Number: AC52-06NA25396
• OSTI ID: 1329860
• Report Number(s): LA-UR--15-20879
• Journal Information: Journal of Fluids Engineering, Journal Name: Journal of Fluids Engineering Journal Issue: 7 Vol. 138; ISSN 0098-2202
• Publisher: American Association of Mechanical Engineers (ASME)
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
Density
Energy dissipation
Mach number
Shock (Mechanics)
Shock tubes
Time series
Turbulence
Vorticity