The (not so simple!) chain fountain

Rogério Martins, CMA/FCT/UNL


Data: 8/2/2018

Hora: 15h00

Local: Sala de seminários - Edifício VII, FCT-UNL



Given a sufficiently long bead chain in a cup, if we pull the end of the chain over the rim of the cup, the chain tends to continuously 'flow' out of the cup, under gravity, in a common siphon process. Surprisingly enough, under certain conditions, the chain forms a fountain in the air! This became known as the Mould effect, after Steve Mould who discovered this phenomenon and made this experiment famous on YouTube, in a video that went viral. We will observe the chain fountain experiment alive and discuss the reason for the emergence of this fountain, that remains unclear.


In this seminar, we raise some open problems that can be of interest to people working in PDEs or numerical analysis.