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arXiv · 2603.09494

Butter on a hot pan: self-regulating dynamics of melt-lubricated sliding

Edoardo Bellincioni·Simon Biermann·Jacco H. Snoeijer·Leen van Wijngaarden·Sander G. Huisman
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Abstract

When solids melt while sliding down heated inclines, their motion is governed by a complex coupling between heat transfer, phase change, gravity and viscous dissipation. Despite relevance across a variety of domains, like kitchen physics, geophysics, tribology, and manufacturing, this coupled problem lacks understanding and quantitative experimental validation. Here we report experiments with ice and paraffin wax on a temperature-controlled ramp that achieve terminal velocities from 0.01 m/s to 2 m/s across wide parameter ranges. We develop a theoretical model that captures the self-regulating feedback between melt-layer thickness, sliding velocity, and heat transfer. Without any adjustable parameters, our model collapses all measurements, validating the fundamental mechanism and enabling predictions for analogous systems.

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Edoardo Bellincioni, Simon Biermann, Jacco H. Snoeijer, Leen van Wijngaarden, Sander G. Huisman. 2026-03-10. Butter on a hot pan: self-regulating dynamics of melt-lubricated sliding. https://arxiv.org/abs/2603.09494

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