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arXiv · 1110.1500

Wavy regimes of film flow down a fibre

Christian Ruyer-Quil·Serafim Kalliadasis
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Abstract

We consider axisymmetric traveling waves propagating on the gravity-driven flow of a liquid down a vertical fibre. Our starting point is the two-equation model for the flow derived in the study by Ruyer-Quil \emph{et al.} [\emph{J. Fluid Mech.} {\bf 603}, 431 (2008)]. The speed, amplitude and shape of the traveling waves are obtained for a wide range of parameters by using asymptotic analysis and elements from dynamical systems theory. Four different regimes are identified corresponding to the predominance of four different physical effects: Advection by the flow, azimuthal curvature, inertia and viscous dispersion. Construction of the traveling-wave branches of solutions reveals complex transitions from one regime to another. A phase diagram of the different regimes in the parameter space is oferred.

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Christian Ruyer-Quil, Serafim Kalliadasis. 2011-10-07. Wavy regimes of film flow down a fibre. https://doi.org/10.1103/physreve.85.046302

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