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Updated: May 9, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
Thermally driven flows between a Leidenfrost solid and a ratchet surface.
Steffen Hardt1, Sudarshan Tiwari, Tobias Baier
1Center of Smart Interfaces, TU Darmstadt, Petersenstrasse 17, D-64287 Darmstadt, Germany.
Summary
Thermally driven flows have minimal impact on Leidenfrost solids
Area of Science:
- Fluid dynamics
- Thermodynamics
- Statistical mechanics
Background:
- Leidenfrost solids exhibit unique behaviors on ratchet surfaces.
- Previous studies suggested thermally driven flows could propel these objects.
- Understanding propulsion mechanisms is key for micro-device applications.
Purpose of the Study:
- To investigate the role of thermally driven flows in Leidenfrost solid propulsion.
- To contrast findings with previous analyses on this topic.
- To identify the dominant propulsion mechanism for Leidenfrost solids on ratchet surfaces.
Main Methods:
- Numerical solution of the Boltzmann equation.
- Analysis of flow patterns and vortex formation.
- Quantification of thrust contributions from different flow types.
Main Results:
- Flow patterns are dominated by vortices at ratchet teeth edges.
- Thermally driven flows contribute insignificantly to propulsion.
- Pressure-driven flow from sublimation is the primary thrust source.
Conclusions:
- Thermally driven flows are not the main driver for Leidenfrost solid propulsion.
- Sublimation-induced pressure gradients dominate the thrust.
- This finding contrasts with prior theoretical claims.
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