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arXiv · 2110.00333

Universality of stretching separation

David Baumgartner·Günter Brenn·Carole Planchette
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Abstract

We develop a parameter-free model for the fragmentation of drops colliding off-center. The prediction is excellent over a wide range of liquid properties. The so-called stretching separation is attributed to the extension of the merged drop above a critical aspect ratio of {3.25}. The evolution of this aspect ratio {is influenced by the liquid viscosity} and can be interpreted via an energy balance. This approach is then adapted to drop-jet collisions, which we model as consecutive drop-drop collisions. {The fragmentation criterion is similar the one observed at drop-drop collisions}, while the evolution of the stretched jet aspect ratio is modified to account for the different flow fields and geometry.

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David Baumgartner, Günter Brenn, Carole Planchette. 2021-10-01. Universality of stretching separation. https://doi.org/10.1017/jfm.2022.107

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