PhD Defense Zoe Barbeau “Two-Phase Shear Layers and Liquid Sheet in an Airstream in the Compressible Regime”

Atomization is the process of break-up of a liquid sheet or jet co-flowing with air streams into a collection of droplets with a wide range of applications from industrial to power generation. The application of interest is air-blast atomization, relevant to fuel injection, where the co-flowing airstream is at high speeds where compressibility may affect atomization. This presentation covers the extension of a high-order compact finite difference framework to compressible, two-phase flows for simulation of atomization and the study of temporal two-phase shear layers and liquid sheets in an airstream. The effect of compressibility on two-phase shear layers and liquid sheets in an airstream is examined in the linear regime through linear stability analysis and by simulation with the compact scheme framework in the nonlinear regime. In contrast to behavior of compressible, single phase shear layers, no significant suppression effect with increasing compressibility is observed at high densities for the two-phase shear layer in the linear and nonlinear regime. Effects of parameters such as density ratio, gas flow Reynolds number, and Weber number on the atomization behavior are also explored.