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On a liquid drop "falling" inside a heavier miscible fluid

Paul K. Buah-Bassuah·René Rojas·Stefania Residori·Fortunato Tito Arecchi
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Abstract

We report a new type of drop instability, where the density difference between the drop and the solvent is negative. We show that the drop falls inside the solvent down to a minimum height, then fragmentation takes place and secondary droplets rise up to the surface. We have developed a theoretical model that captures the essential of the phenomenon and predicts the correct scalings for the rise-up time and the minimum height.

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Paul K. Buah-Bassuah, René Rojas, Stefania Residori, Fortunato Tito Arecchi. 2005-12-06. On a liquid drop "falling" inside a heavier miscible fluid. https://arxiv.org/abs/nlin/0512011

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