Rayleigh-Taylor instability of a thin elastic solid impulsively loaded by a shock wave

Growth of instability in a thin elastic solid accelerated by a gasdynamic shock tube is studied experimentally. Silicone elastomers of different thicknesses, initial perturbation wavelengths, and initial perturbation amplitudes are examined—the initial perturbations are sinusoidal. A silicone elastomer material (Ecoflex 00-30) is used because of its hyperelasticity and very low shear modulus, properties which facilitate examining the phenomenon of interest in a laboratory-scale, low-pressure shock tube. The samples are lightly supported in the shock tube test section to avoid the influence of boundary effects. The gas shock reflects off the sample, causing it to accelerate due to the reflected shock pressure. The dynamics of the sample is recorded using high-speed videography and photonic Doppler velocimetry (PDV) with the PDV configuration tracking the velocity of individual perturbation peaks and troughs of the sample free surface. The experimental results are compared against analytical Rayleigh-Taylor stability growth rates found in the literature.