SUMMARY

This work investigates the variable density mixing in an explosively driven environment due to the fluid instabilities at the material interfaces. Specifically, diverging Richtmyer-Meshkov (impulsive-acceleration environment) and Rayleigh-Taylor (variable-acceleration environment) instabilities (present in a supernova event, inertial confinement fusion environment) are studied through the use of advanced high-speed diagnostics in carefully designed laboratory experiments. The blast-driven instability morphology is presented through a time development of Mie scattering images, and steps through the parameter space (varying density ratio and driver speed), highlighting the development of the structures that form during mixing. Velocity fields in the blast-driven instability have been captured for the first time using the high temporal resolution PIV technique. Subsequent analysis of the distribution of kinetic energy, the transition to turbulence, and the characteristic growth of the instability are discussed. This study furthers understanding of how blast-driven instability pertains to supernova and inertial confinement fusion science. The technical objectives are to: 1. Observe the turbulent length scales necessary for mixing transition to occur after a critical Reynolds number is achieved 2. Measure and quantify the growth model for the blast-driven mixing environment 3. Acquire measurements of velocity fields from the Blast Driven Instability for the first time to develop an understanding of the dynamics of the flow field.