Subgrid-scale modeling of droplet bag breakup

We present volume of fluid simulations of an impulsively accelerated liquid drop that undergoes bag regime breakup. While the drop is resolved by as few as ten cells across the initial diameter, the formation of the resulting micron-thickness liquid film is still captured using a dual-plane interface reconstruction. After the liquid film is punctured, a Taylor-Culick retraction model is applied to it in conjunction with a droplet shedding model to predict the time-resolved fragmentation of the film. The resulting droplet size distributions are compared to those from experiments and theoretical work. Finally, the film breakup model is integrated into a simulation of full-scale turbulent air-blast atomization to demonstrate the model's scalability.