J'étudie comment les petits corps liquides (jets, films, gouttes, bulles…) se forment, déforment ou fragmentent. Ces objets, fortement contraints par leur interface et éphémères, sont partout. Ils engendrent les embruns, par l'éclatement des bulles à la surface des océans; sont au coeur des sources de lumière ultra-violette nécessaires à la gravure des puces électroniques futures; amorcent et contrôlent l'ébullition et la condensation des liquides…

Les recherches en cours incluent aussi des particules solides.

I study how small liquid objects (jets, films, drops, bubbles…) form, deform and possibly fragment.

The interface-dominated dynamics of these objects is everywhere in nature, daily life and technology. It dictates the size of the oceans aerosols, which result from the life and death of surface bubbles; it is essential to creating shorter wavelength light for grabing the next generation of microchips; it controls bubble and droplet nucleation, hence the boiling and condensation of liquids…

Current research topics concern jets, drops, films… and solid particules.

Interface destabilization & fragmentation

Mixing in suspensions

with M. Souzy & B. Metzger Dispersing and mixing a dye – or a hot spot – inside a viscous liquid within a realistic amount of time usually requires a meticulous stirring. In a particlulate suspension, a gentle shear is sufficient: collisions between the particles create a chaotic flow which spontaneously stirs and mixes the suspending liquid. Stretching and mixing in sheared particulate suspensions
Souzy, Lhuissier, Villermaux & Metzger (2017)

Liquid sheets and curtains

with P. Brunet & S. Dorbolo J-M. Gordillo V. Pistre & E. Villermaux Savart sheets and bells, first studied by Savart in the early 19th, are beautiful and easily controlable dynamic fluid objects formed by letting a jet impact onto a solid with similar size. They prove to be an ideal tool for studying the dynamics of folding, the destabilization of the edge, and the fragmentation of suspended liquid sheets. Blowing a liquid curtain. Lhuissier, Brunet & Dorbolo (2016)
On the cusps bordering liquid sheets. Gordillo, Lhuissier & Villermaux (2014)
The viscous Savart sheet. Villermaux, Pistre & Lhuissier (2013)
‘Effervescent’ atomization in 2 dimensions. Lhuissier & Villermaux (2013)
Crumpled water bells. Lhuissier & Villermaux (2012)

Drop impacts

with A. Klein & H. Gelderblom C. Sun, A. Prosperetti & D. Lohse A drop impacting onto a surface deforms, and either spreads, rebounds or fragments depending on its size, velocity, surface tension, etc… This not only owes for an impact with a solid but also for a drop impacting onto an immiscible liquid bath, or for a falling opaque drop hit by a laser pulse. Drop deformation by laser-pulse impact. Gelderblom et al. (2016)
Drop shaping by laser-pulse impact. Klein et al. (2015)
Laser impact on a drop. Klein et al. (2015)
Drop fragmentation at impact onto a bath of an immiscible liquid
Lhuissier, Sun, Prosperetti & Lohse. (2013)

Visco-elastic surface flows

with B. Néel & L. Limat Adding minute fraction of long unbranched polymers in water tremendously affects the rheology, hence the dynamics of small liquid objects. A jet of such a visco-elastic liquid may for instance develop wings on impact and form a polygonal liquid sheet or a polygonal hydraulic jump. Visco-elasticity also drastically affects the flow and stability of liquid curtains used in coating processes. Viscoelasticity breaks the symmetry of impacting jets
Lhuissier, Néel & Limat (2014)

Levitation of a drop

with Y. Tagawa, T. Tran & C. Sun A drop of liquid gently deposited onto a moving and inclined surface naturally deforms to accomodate the air flow. This allows the steady levitation, or ‘surf’, of the drop over a micrometer-thick air cushion. Levitation of a drop over a moving surface
Lhuissier, Tagawa, Tran & Sun (2013)

Liquid films & bubbles bursting

with E. Villermaux Both flat soap films formed in foams, or by withdrawing a frame out of a pool, and the curved films formed when air bubbles rise to the ocean surface are prone to draining, nucleating a hole and atomizing in many small droplets once a hole has opened. This is, for instance, the origin of sea-spray. Bursting bubble aerosols. Lhuissier & Villermaux (2012)
The destabilization of an initially thick liquid sheet edge. Lhuissier & Villermaux (2011)
Soap films burst like flapping flags. Lhuissier & Villermaux (2009)
Bursting bubbles. Lhuissier & Villermaux (2009)
Destabilization of flapping sheets: The surprising analogue of soap films
Lhuissier & Villermaux. (2009)

Phase change & others

Dew collection on textured surfaces

with A. Mongruel, L. Royon & D. Beysens Dew, i.e. atmospheric water condensing on solid surfaces facing a clear night sky, forms droplets that do not drain until they grow up to typically 1 mm in size. Dew collection, motivated by drinking purpose in dry areas, crucially depends on this amount of water required to prime the flow, which compares to the whole night condensation. Textured surfaces represent one promising strategy to reduce this priming water and improve dew collection.

Bubble nucleation on rubbing solids

with S. Wildeman, T. Ito, C. Sun, A. Prosperetti & D. Lohse Gently rubbing two immersed solids together may nucleate gas/vapor bubbles which subsequently grow. By controling the rubbing force and velocity this permits forming a regular bubble trail, that is, ‘writing with bubbles’. Tribonucleation of bubbles. Wildeman, Lhuissier, Sun, Lohse & Prosperetti (2014)
Vapor bubble nucleation by rubbing surfaces: Molecular dynamics simulations
Ito, Lhuissier, Wildeman & Lohse. (2014)

Boiling of highly superheated liquids

with M. van Limbeek, C. Sun, A. Prosperetti & D. Lohse A drop of a volatile liquid immersed in a non-volatile liquid may be heated far above its usual boiling temperature before it actually boils. When the first vapor bubble eventually forms, the boiling dynamics is determined by the wetting properties of the two liquids. Explosive boiling? van Limbeek, Lhuissier, Sun, Prosperetti & Lohse (2013)

Micro & nano-bubbles

with X. Zhang, O. Enríquez, C. Sun & D. Lohse Surface nano-bubbles are gas volumes with submicrometer sizes that can form on a hydophilic substrate immersed in water. Surface nanobubbles nucleate microdroplets. Zhang, Lhuissier, Sun & Lohse (2014)
Spatial organization of surface nanobubbles and its implications in their formation process. Lhuissier, Zhang & Lohse (2014)
Deactivation of microbubble nucleation sites by alcohol-water exchange
Zhang, Lhuissier, Enríquez, Sun & Lohse (2013)