Containerless solidification, in which the melt is confined by its own surface tension, is an
important technique by which very pure materials can be produced. The form of the solidified
product is sensitive to conditions at the tri-junction between the solid, the melt and the
surrounding vapor. An understanding of the dynamics of tri-junctions is therefore crucial to
the modelling and prediction of containerless solidification systems. We consider
experimentally and analytically the simple system of a liquid droplet solidifying on a cold …