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arXiv · 1501.00935

Mathematical Modelling of Tyndall Star Initiation

Andrew A. Lacey·Matthew G. Hennessy·Peter Harvey·Richard F. Katz
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Abstract

The superheating that usually occurs when a solid is melted by volumetric heating can produce irregular solid-liquid interfaces. Such interfaces can be visualised in ice, where they are sometimes known as Tyndall stars. This paper describes some of the experimental observations of Tyndall stars and a mathematical model for the early stages of their evolution. The modelling is complicated by the strong crystalline anisotropy, which results in an anisotropic kinetic undercooling at the interface; it leads to an interesting class of free boundary problems that treat the melt region as infinitesimally thin.

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Andrew A. Lacey, Matthew G. Hennessy, Peter Harvey, Richard F. Katz. 2015-07-14. Mathematical Modelling of Tyndall Star Initiation. https://doi.org/10.1017/s095679251500042x

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