``Effervescent'' Atomization in two dimensions

A planar \emph{Savart} water sheet uniformly seeded with small air bubbles in large surface concentration is studied as a model experiment of the so-called ``effervescent'' atomization process. This two-dimensional setup allows for a quantitative observation of all the steps of the sheet disintegration into a collection of disjointed droplets. The bubbles are heterogeneous nucleation sites which puncture the sheet forming growing holes. The dynamics of the holes opening competes with the simultaneous nucleation rate of new holes in a statistically stationary fashion. The liquid constitutive of the sheet is then transitorily concentrated into a web of ligaments of various lengths and diameters, at the junction between adjacent holes. Their break-up produces the final spray. We provide a complete description of the ligaments web statistics in the case where nucleation is synchronous, and show that the drop size dispersion from the breakup of a single ligament is responsible for the shape of the resulting overall spray drop size distribution.