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arXiv · 1208.5657

Thermally-driven flows between a Leidenfrost solid and a ratchet surface

Steffen Hardt·Sudarshan Tiwari·Tobias Baier
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Abstract

The significance of thermally-driven flows for the propulsion of Leidenfrost solids on a ratchet surface is studied based on a numerical solution of the Boltzmann equation. In contrast to a previous analysis, it is found that no significant thermal creep flow is established. Instead, the flow pattern is dominated by thermal edge and thermal-stress slip flow, the latter being directed opposite to thermal creep flow. However, in total thermally-induced flows only make a minor contribution to the propulsion of Leidenfrost solids on ratchet surfaces which is dominated by the pressure-driven flow due to the sublimating solid.

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Steffen Hardt, Sudarshan Tiwari, Tobias Baier. 2012-08-28. Thermally-driven flows between a Leidenfrost solid and a ratchet surface. https://doi.org/10.1103/physreve.87.063015

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