Seminars

PMMH’s weekly seminar is held every Friday at 11 am (map)

Contact :
Stéphane Perrard
Etienne Reyssat
Virgile Thiévenaz
responsables-seminaires (arobase) pmmh.espci.fr

PMMH
BARRE CASSAN
BAT A 1ER ETAGE CASE 18
7 QUAI SAINT BERNARD
75005 PARIS
France

Tel : (33) 1 40 79 45 22


Séminaire PMMH - Anaïs Gauthier, IPR Rennes, CNRS

Vendredi 19 septembre de 11h00 à 12h00 - Salle réunion PMMH 1

Capillary choreographies at low-Friction interfaces

From Leidenfrost baths to soap films

The motion of millimetre-sized objects trapped at the liquid-air interfaces is a familiar phenomenon, seen in the clumping of cereals in a bowl or of bubbles at the surface of a sparkling drink. The deformation of the interface typically generates attractive forces between the particles, while friction with the underlying liquid strongly damp the motion.

In this talk, we will explore the dynamics of particles placed on two unusual interfaces, on which the friction is drastically reduced.
The first system is an evaporating bath of liquid nitrogen. When deposited on the cryogenic bath, ambient temperature particles are maintained in levitation by the vapour escaping from the interface. The particles spontaneously self-propel, moving in straight lines at a velocity of a few cm/s. We will explain the mechanism underlying this motion, and analyse the orbiting trajectories that appear when two particles interact.
The second system is an horizontal soap film. Here again, friction is extremely weak, while the attractive force now extends over much longer range. We study the origin of the friction, and measure the interaction force by combining two methods : analyzing particle dynamics, and using the magnetic actuation of paramagnetic beads. We show that at large distances (a few centimeters), the attraction results from film-scale deformations due to the weight the beads. At small distances (a few millimeters), the interaction force suddenly increases due to the capillary interaction between the menisci surrounding the particles.

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Seminars  (10)

Information for the speakers

The audience is composed of people with rather heterogeneous backgrounds including specialists in solids, fluids, granular flows, statistical physics... so the idea is to keep your talk understandable by people not necessarily working in your field... The seminar time slot runs from 11am to noon so the best is to make the talk last around 45 minutes to leave some time for discussion.

Archive 1996-2011
Other seminars in Paris and its surroundings :

Link to cofee seminar (internal, every Thursday)


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Seminars (3)

Contact

Directeur : Ramiro GODOY DIANA
Codirecteur : Laurent DUCHEMIN
Administratrice : Frédérique AUGER (01 40 79 45 22)
Gestionnaire : Claudette BAREZ (01 40 79 58 53)
Courriel : dir (arobase) pmmh.espci.fr
Téléphone : 01 40 79 45 22
Adresse : PMMH UMR 7636 CNRS, ESPCI Paris-PSL, Sorbonne Université, Université Paris Cité
7 Quai Saint Bernard, Barre Cassan Bât A 1er étage Case 18, 75005 Paris