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arXiv · cond-mat/0403043

Dynamical Model for Chemically Driven Running Droplets

Uwe Thiele·Karin John·Markus Bär
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Abstract

We propose coupled evolution equations for the thickness of a liquid film and the density of an adsorbate layer on a partially wetting solid substrate. Therein, running droplets are studied assuming a chemical reaction underneath the droplets that induces a wettability gradient on the substrate and provides the driving force for droplet motion. Two different regimes for moving droplets -- reaction-limited and saturated regime -- are described. They correspond to increasing and decreasing velocities with increasing reaction rates and droplet sizes, respectively. The existence of the two regimes offers a natural explanation of prior experimental observations.

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BibTeXRIS

Uwe Thiele, Karin John, Markus Bär. 2004-05-07. Dynamical Model for Chemically Driven Running Droplets. https://doi.org/10.1103/physrevlett.93.027802

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