ESPCI web site
PMMH’s weekly seminar is held every Friday at 11 am (map)
Stéphane Perrard
Etienne Reyssat
Virgile Thiévenaz
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 - Matilda Backholm (Aalto Univ., Helsinki, Finland)
When honey moves faster than water
The viscosity of a fluid is well known to limit its flow : the more viscous a droplet, the slower it moves [1,2]. Here, we show that this intuitive rule breaks down in a confined liquid-repellent geometry. A gravity-driven, highly viscous glycerol droplet placed in a sealed superhydrophobic capillary moves more than 10 times faster than a low-viscosity water droplet [3]. This anomalous, viscosity-enhanced droplet motion is caused by a viscosity-suppressed deformation of the droplet-air interface. We find that the air film (plastron) trapped within the micro/nanostructure of the superhydrophobic coating plays an interesting and important role in controlling fluid flow beyond a mere reduction in contact area and friction.
[1] D. Richard and D. Quéré, Europhys. Lett. 48 (1999).
[2] T. Mouterde, P. S. Raux, C. Clanet, and D. Quéré, Proc. Natl. Acad. Sci. USA 116 (2019).
[3] M. Vuckovac, M. Backholm, J. V. I. Timonen, and R. H. A. Ras, Science Advances 6 (2020).
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.
- Séminaires ESPCI-ENS de biophysique
- Séminaires du Département de Physique de l’ENS
- Séminaires du Laboratoire d’Hydrodynamique de l’X
- Séminaire de Mécanique d’Orsay (page web FAST)
- Séminaire de Mécanique d’Orsay (page web LIMSI)
- Séminaire de Mécanique des Fluides de l’Institut Jean le Rond d’Alembert
- Séminaires du laboratoire MSC, Paris VII
- Séminaires Gulliver
Link to cofee seminar (internal, every Thursday)
