Packings of monodisperse emulsions in flat microfluidic channels.

In the lateral confinement of a flat microfluidic channel, monodisperse emulsion droplets spontaneously self-organize in a variety of topologically different packings. The explicit construction of mechanically equilibrated arrangements of effectively two-dimensional congruent droplet shapes reveals the existence of multiple mechanical equilibria depending on channel width W, droplet area A{d}, and volume fraction φ of the dispersed phase. The corresponding boundaries of local or global stability are summarized in a packing diagram for congruent droplet shapes in terms of the dimensionless channel width w=W/sqrt[A_{d}] and φ.