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arXiv · 1401.7452

Leidenfrost Gas Ratchets Driven by Thermal Creep

Alois Würger
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Abstract

We show that thermal creep is at the origin of the recently discovered Leidenfrost ratchet, where liquid droplets float on a vapor layer along a heated sawtooth surface and accelerate to velocities of up to 40 cm=s. As the active element, the asymmetric temperature profile at each ratchet summit rectifies the vapor flow in the boundary layer. This mechanism works at low Reynolds number and provides a novel tool for controlling gas flow at nanostructured surfaces.

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Alois Würger. 2014-01-29. Leidenfrost Gas Ratchets Driven by Thermal Creep. https://doi.org/10.1103/physrevlett.107.164502

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