Role of the channel geometry on the bubble pinch-off in flow-focusing devices.

نویسندگان

  • Benjamin Dollet
  • Wim van Hoeve
  • Jan-Paul Raven
  • Philippe Marmottant
  • Michel Versluis
چکیده

The formation of bubbles by flow focusing of a gas and a liquid in a rectangular channel is shown to depend strongly on the channel aspect ratio. Bubble breakup consists in a slow linear 2D collapse of the gas thread, ending in a fast 3D pinch-off. The 2D collapse is predicted to be stable against perturbations of the gas-liquid interface, whereas the 3D pinch-off is unstable, causing bubble polydispersity. During 3D pinch-off, a scaling w_(m) approximately tau(1/3) between the neck width w_(m) and the time tau before breakup indicates that breakup is driven by the inertia of both gas and liquid, not by capillarity.

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عنوان ژورنال:
  • Physical review letters

دوره 100 3  شماره 

صفحات  -

تاریخ انتشار 2008