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arXiv · 1612.08383

Viscous fingering and dendritic growth under an elastic membrane

Lucie Ducloue·Andrew Hazel·Draga Pihler-Puzovic·Anne Juel
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Abstract

We investigate the viscous fingering instability that arises when air is injected from the end of an oil-filled, compliant channel. We show that induced axial and transverse depth gradients foster novel pattern formation. Moreover, the steady propagation of the interface allows us to elucidate the nonlinear saturation of a fingering pattern first observed in a time-evolving system (Pihler-Puzovic et al. PRL 108, 074502, 2012): the wavelength is set by the viscous fingering mechanism, but the amplitude is inversely proportional to the tangent of the compliant wall's inclination angle.

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Lucie Ducloue, Andrew Hazel, Draga Pihler-Puzovic, Anne Juel. 2016-12-26. Viscous fingering and dendritic growth under an elastic membrane. https://doi.org/10.1017/jfm.2017.468

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