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Droplet detachment and bead formation in visco-elastic fluids

C. Wagner·Y. Amarouchene·D. Bonn·J. Eggers
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Abstract

The presence of a very small amount of high molecular weight polymer significantly delays the pinch-off singularity of a drop of water falling from a faucet, and leads to the formation of a long-lived cylindrical filament. In this paper we present experiments, numerical simulations, and theory which examines the pinch-off process in the presence of polymers. The numerical simulations are found to be in excellent agreement with experiment. As a test case, we establish the conditions under which a small bead remains on the filament; we find that this is due to the asymmetry induced by the self-similar pinch-off of the droplet.

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C. Wagner, Y. Amarouchene, D. Bonn, J. Eggers. 2004-07-20. Droplet detachment and bead formation in visco-elastic fluids. https://doi.org/10.1103/physrevlett.95.164504

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