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arXiv · 2006.11065

Elucidating the mechanism of step-emulsification

Andrea Montessori·Marco Lauricella·Sauro Succi·Elad Stolovicki·David A. Weitz
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Abstract

Three-dimensional, time-dependent direct simulations of step emulsification micro-devices highlight two essential mechanisms for droplet formation: first, the onset of an adverse pressure gradient driving a back-flow of the continuous phase from the external reservoir to the micro-channel. Second, the striction 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 stabilising effect of dynamic pressure. This suggests a new criterion for dripping-jetting transition, based on local values of the Capillary and Weber numbers.

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Andrea Montessori, Marco Lauricella, Sauro Succi, Elad Stolovicki, David A. Weitz. 2020-06-19. Elucidating the mechanism of step-emulsification. https://doi.org/10.1103/physrevfluids.3.072202

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