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Accueil du site > Séminaires > Archives séminaires > Séminaires 2021 > MSC Visio-Seminar. February 8th, 2021. Giuseppe Pucci (CNR-Nanotec, Calabria, Italy) : "Water sliders, capillary attraction and capillary surfers".

MSC Visio-Seminar. February 8th, 2021. Giuseppe Pucci (CNR-Nanotec, Calabria, Italy) : "Water sliders, capillary attraction and capillary surfers"

Sauf mention contraire, les séminaires et les soutenances se déroulent à 11h30 en salle 454A du bâtiment Condorcet.

February 8th 2021. 11h30

There will be a live diffusion with Zoom. Contact Michael Berhanu to attend the video seminar.

Water sliders, capillary attraction and capillary surfers

Giuseppe Pucci

Consiglio Nazionale delle Ricerche, Istituto di Nanotecnologia

CNR-Nanotec, Calabria, Italy

c/o Dipartimento di Fisica, Università della Calabria, Italy

A body can be supported at the water-air interface by virtue of the equilibrium among its weight, surface tension and hydrostatic forces. Quantifying the forces experienced by small floating bodies is of critical importance for understanding the motion of living organisms at the water-air interface and can inform the design of aerial-aquatic microrobots for environmental exploration and monitoring. In this seminar, I present recent work on the statics and dynamics of capillary bodies.

In the first part, we experimentally show that the motion of centimetric sliders is dominated by skin friction due to the boundary layer that forms in the fluid beneath the body. In the second part, we directly measure and rationalize the capillary attraction force between centimetric disks resting at the air-water interface. In the third part, we show that a capillary body self-propels on the surface of a vibrating bath when its rotational symmetry is broken. The self-propulsion of this capillary surfer is due to the difference in momentum of the waves generated by the fore and the aft of the body. Capillary surfers interact with one another through their mutual capillary wavefield and resultant fluid flows, and exhibit a rich set of collective modes characterized by a discrete number of equilibrium spacings. These results open the door to further investigations of this novel active system at the fluid interface.

This work has been done in collaboration with Ian Ho and Daniel M. Harris at Brown University and Anand U. Oza at New Jersey Institute of Technology.

Contact : Équipe séminaires / Seminar team - Published on / Publié le 27 janvier 2021

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