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arXiv · 0807.2112

Capillary filling with randomly coated walls

Fabiana Diotallevi·Andrea Puglisi·Antonio Lamura·Sauro Succi
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Abstract

The motion of an air-fluid interface through an irregularly coated capillary is studied by analysing the Lucas-Washburn equation with a random capillary force. The pinning probability goes from zero to a maximum value, as the interface slows down. Under a critical velocity, the distribution of waiting times $τ$ displays a power-law tail $\sim τ^{-2}$ which corresponds to a strongly intermittent dynamics, also observed in experiments. We elaborate a procedure to predict quantities of experimental interest, such as the average interface trajectory and the distribution of pinning lengths.

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Fabiana Diotallevi, Andrea Puglisi, Antonio Lamura, Sauro Succi. 2008-07-14. Capillary filling with randomly coated walls. https://doi.org/10.1088/1742-5468%2F2009%2F02%2Fl02001

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