Elucidating the mechanism of step emulsification

作者:Montessori Andrea*; Lauricella Marco; Succi Sauro; Stolovicki Elad; Weitz David
来源:Physical Review Fluids, 2018, 3(7): 072202.
DOI:10.1103/PhysRevFluids.3.072202

摘要

Three-dimensional, time-dependent direct simulations of step emulsification microdevices highlight two essential mechanisms for droplet formation: first, the onset of an adverse pressure gradient driving a backflow of the continuous phase from the external reservoir to the microchannel, and second, the stnction of the flowing jet which leads to its subsequent rupture. It is also shown that such a rupture is delayed and eventually suppressed by increasing the flow speed of the dispersed phase within the channel, due to the stabilizing effect of dynamic pressure. This suggests a new criterion for dripping-jetting transition, based on local values of the capillary and Weber numbers.

  • 出版日期2018-7-30