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arXiv · 1906.00677

Self-organised dip-coating patterns of simple, partially wetting, nonvolatile liquids

Walter Tewes·Markus Wilczek·Svetlana V. Gurevich·Uwe Thiele
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Abstract

When a solid substrate is withdrawn from a bath of simple, partially wetting, nonvolatile liquid, one typically distinguishes two regimes, namely, after withdrawal the substrate is macroscopically dry or homogeneously coated by a liquid film. In the latter case, the coating is called a Landau-Levich film. Its thickness depends on the angle and velocity of substrate withdrawal. We predict by means of a numerical and analytical investigation of a hydrodynamic thin-film model the existence of a third regime. It consists of the deposition of a regular pattern of liquid ridges oriented parallel to the meniscus. We establish that the mechanism of the underlying meniscus instability originates from competing film dewetting and Landau-Levich film deposition. Our analysis combines a marginal stability analysis, numerical time simulations and a numerical bifurcation study via path-continuation.

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Walter Tewes, Markus Wilczek, Svetlana V. Gurevich, Uwe Thiele. 2019-06-03. Self-organised dip-coating patterns of simple, partially wetting, nonvolatile liquids. https://doi.org/10.1103/physrevfluids.4.123903

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