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arXiv · 1001.2417

Transport of free surface liquid films and drops by external ratchets and self-ratcheting mechanisms

Uwe Thiele·Karin John
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Abstract

We discuss the usage of ratchet mechanisms to transport a continuous phase in several micro-fluidic settings. In particular, we study the transport of a dielectric liquid in a heterogeneous ratchet capacitor that is periodically switched on and off. The second system consists of drops on a solid substrate that are transported by different types of harmonic substrate vibrations. We argue that the latter can be seen as a self-ratcheting process and discuss analogies between the employed class of thin film equations and Fokker-Planck equations for transport of discrete objects in a 'particle ratchet'.

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Uwe Thiele, Karin John. 2010-01-14. Transport of free surface liquid films and drops by external ratchets and self-ratcheting mechanisms. https://doi.org/10.1016/j.chemphys.2010.07.011

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