Dynamics of Rayleigh-Taylor driven flows at high Atwood numbers

For the first time, detailed simultaneous density and velocity turbulent statistics for Rayleigh-Taylor instabilities at Atwood number of 0.75 are measured. A new density probe capable of measuring gas volumetric concentration directly is used in parallel to a three-wire probe to obtain instantaneous density and velocity components simultaneously. Particle Image Velocimetry (PIV) is also implemented to obtain field-wise measurements. The self-similarity behavior of the velocity statistics, corresponding probability density function (PDF) and spectra are presented. Mie-scattering images taken in both stream-wise and span-wise direction at different instability times have illustrated the turbulent structures visible in the instability.