Monodisperse microbubbling: Absolute instabilities in coflowing gas-liquidjets

Contrary to liquid jets, gas jets in coflowing liquid streams are highly un stable. When these gas jets are sufficiently small, their breakup into micr obubbles is strongly self-locked at a certain frequency. This provokes a co ntinuous streaming of microbubbles with perfectly homogeneous and controlla ble size. In this work, we describe theoretically the absolute instability origin of the dynamical behavior of these gas jets surrounded by a coflowin g liquid stream, and give the explanation to the extremely elusive nature o f a gas ligament. (C) 2001 American Institute of Physics.