76th Annual Meeting of the APS Division of Fluid Dynamics (November 19, 2023 — November 21, 2023)

V0029: Fragmentation of a graphite floating raft by water surface waves.

Authors

• Michael Berhanu, Matiere et Système Complexes, Université Paris Cité, CNRS (UMR 7057)
• Louis Saddier, Ecole Normale Superieure Paris Saclay, Université Paris Saclay
• Ambre Palotai, Ecole Normale Superieure, Université PSL
• Mathéo Aksil, Ecole Normale Superieure, Université PSL
• Michel Tsamados, Centre for Polar Observation and Modelling, University College London

DOI: https://doi.org/10.1103/APS.DFD.2023.GFM.V0029

Fragmentation of a graphite floating raft by water surface waves.

When particles of a few tens of microns are spread on the surface of water, they aggregate unde rthe action of capillary forces and form a thin floating membrane, a particle raft. In an experimental tank with a raft made of graphite powder, we generate gravity surface waves, whose wavelength is very large compared to the thickness of the raft. For a sufficiently strong wave amplitude, the raft breaks up progressively by producing fragments whose sizes decrease on a time scale long compared to the period of the wave. The visual appearance of the fragments surrounded by open water bears a striking resemblance to the floes produced by the fracturing of sea-ice by waves in the polar oceans. Fragmentation concepts and morphological tools built for sea-ice floes could be applied to our macroscopic analog, on which the entire dynamical evolution is accessible.