Cascades and Nonlinear Processes in Rayleigh-Taylor flows

Dongxiao Zhao, PhD Qualifying Exam, Advised by Professor Hussein Aluie

Hopeman 224

The Rayleigh-Taylor Instability (RTI) occurs when a heavy fluid is accelerated against a lighter fluid and is manifested by the formation of upward-rising bubbles and downward-sinking spikes. It plays an important role in many natural and engineered systems, such as determining the flame propagation speed in supernova explosions, and is considered a major obstacle in inertial confinement fusion (ICF). Much effort has been devoted to understand and model RTI, yet many basic questions remain unsolved, including how energy flows through the multi-scale system. RTI is unsteady, anisotropic, and inhomogeneous, rendering traditional methods from the turbulence literature ill-suited. In my talk, I will outline a research program I am undertaking to map out the energy pathways in RTI using a novel multi-scale analysis framework we have been developing.