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PubMed · 15323952

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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DiffusionLipidsModels, TheoreticalPhysicsSolventsJournal ArticleResearch Support, Non-U.S. Gov't

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Uwe Thiele, Karin John, Markus Bär. 2004-07-09. Dynamical model for chemically driven running droplets.. https://doi.org/10.1103/physrevlett.93.027802

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