Experimental validation of a Richtmyer–Meshkov scaling law over large density ratio and shock strength ranges

Abstract

A universal scaling law for the Richtmyer-Meshkov instability is validated with experimental results covering a wide range of density ratios and shock strengths. These results include the first membraneless, gas-phase, interface experiments for A Ͼ 0.5 and M Ͼ 1.5. The shock-accelerated, sinusoidal interface experiments are conducted in a vertical shock tube with a large square cross section and cover the experimental parameter space: 0.29Ͻ A Ͻ 0.95, 1.1Ͻ M Ͻ 3, and 3.1ϫ 10 4 Ͻ ReϽ 1.4ϫ 10 7 . Results provide growth-rate data for comparison with computational fluid dynamics simulation codes and verify the nondimensional time and amplitude parameters chosen for scaling are the correct ones. Correct scaling is obtained by including a growth-reduction factor that accounts for diffusion at the interface. Planar imaging techniques are used to diagnose the instability development for a nearly single-mode interface, and results are reported for eight scenarios ͑including three distinct gas pairs͒ that span the linear and nonlinear growth regimes. Images from the strongly shocked, high A experiments are the first to provide evidence of bubble-growth suppression due to shock proximity.

Experimental Study of Turbulent Mixing in the Richtmyer-Meshkov Instability

“…These slots are connected to a pair of vacuum pumps, ensuring a rapid outflow of gas. This method to create a flat, membraneless interface is similar to that developed for the University of Arizona shock tube [3] and used previously at the University of Wisconsin [4].…”

Influence of the Richtmyer-Meshkov instability on the kinetic energy spectrum.

“…The experiments are performed at the Wisconsin Shock Tube Laboratory [12]. The shock tube is a downward firing, 9.13 m vertical tube.…”

Computational parametric study of a Richtmyer-Meshkov instability for an inclined interface

“…Facilities using this method employ a shock tube to generate a shock wave which interacts with a fluid interface containing a density perturbation. An oscillation in the fluid interface can create a sinusoidal perturbation as done by Krivets et al [5] and Motl et al [6]. Another interface perturbation method employed in shock tubes is to use a bubble of lighter or heavier gas as used by Ranjan et al [7].…”

“…2 3 2 3 4 5 Various modifications to improve the impulsive model for both light/heavy and heavy/light interfaces have been made by Myer and Blewett [17], and Vandenboomgaerde [18]. A growth reduction factor was proposed based on experiments for a diffuse interface by Motl et al [6].…”

“…The 1D gas dynamic parameters and wave speeds used in these calculations and calculations in the following section are listed in Table III and Table IV below. (6) : ; The non-dimensionalized data from the Richtmyer impulsive model for the Air-SF6 simulations is plotted below in Figure 6. For all mixing width plots the key lists the cases described by the light gas name, the Mach number, excluding the decimal, preceded by the letter M, and inclination angle preceded by the letter A.…”