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arXiv · 1601.04584

Effect of geometry on the dewetting of granular chains by evaporation

Cesare M. Cejas·Lawrence A. Hough·Christian Frétigny·Rémi Dreyfus
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Abstract

Understanding evaporation or drying in granular media still remains complex despite recent advancements. Evaporation depends on liquid transport across a connected film network from the bulk to the surface. In this study, we investigate the stability of film networks as a function of granular packing. Using a controlled experimental approach, we vary the granular packing geometry and show the changes in the height of the liquid film network during evaporation as packing shifts from a loose-packed to a close-packed arrangement. This height can be calculated from an equilibrium between hydrostatic pressure and the pressure difference between two points in the vertical film network. We use a simulation approach to calculate the pressure in both the percolating front and evaporating front within the two-phase zone of air/water mixture. Results show good agreement between the model and the experiment.

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Cesare M. Cejas, Lawrence A. Hough, Christian Frétigny, Rémi Dreyfus. 2016-01-18. Effect of geometry on the dewetting of granular chains by evaporation. https://doi.org/10.1039/c8sm01179f

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