The mayonnaise droplet

Poster (2009, March)

compaction dynamics of magnetized powder

in Physical Review. E : Statistical, Nonlinear, and Soft Matter Physics (2009), 80

Antibubbles, liquid onions and bouncing droplets

in Colloids and Surfaces A : Physicochemical and Engineering Aspects (2009), 344

The mayonnaise droplet

in Chaos (2009)

Hybrid wetting state on micro-waffle textures

in Europhysics Letters (2009), 88

Resonant and rolling droplet

in New Journal of Physics (2008), 10

When an oil droplet is placed on a quiescent oil bath, it eventually collapses into the bath due to gravity. The resulting coalescence may be eliminated when the bath is vertically vibrated. The droplet ... [more ▼]

When an oil droplet is placed on a quiescent oil bath, it eventually collapses into the bath due to gravity. The resulting coalescence may be eliminated when the bath is vertically vibrated. The droplet bounces periodically on the bath, and the air layer between the droplet and the bath is replenished at each bounce. This sustained bouncing motion is achieved when the forcing acceleration is higher than a threshold value. When the droplet has a sufficiently low viscosity, it significantly deforms: spherical harmonic Y-1(m) modes are excited, resulting in resonant effects on the threshold acceleration curve. Indeed, a lower acceleration is needed when I modes with m = 0 are excited. Modes m not equal 0 are found to decrease the bouncing ability of the droplet. A break of degeneracy is observed for the m parameter. In particular, when the mode 1 = 2 and m = 1 is excited, the droplet rolls on the vibrated surface without touching it, leading to a new self-propulsion mode. [less ▲]

A droplet of spectroscopy

Conference (2008, November)

Droplet coalescence in a liquid bath can be delayed by oscillating the surface of the bath vertically (frequency from 20 Hz to 400 Hz), the droplet bounces on the interface [1,2]. A low viscous oil ... [more ▼]

Droplet coalescence in a liquid bath can be delayed by oscillating the surface of the bath vertically (frequency from 20 Hz to 400 Hz), the droplet bounces on the interface [1,2]. A low viscous oil droplet is dropped on a high viscous oil bath. We observe that the conditions for bouncing depends on the frequency, more precisely we observe resonance when the eigenfrequency of the droplet is excited. In some conditions, droplet presents a non axi-symmetric mode of deformation. That leads to a rotation of the drop and to a horizontal displacement. [less ▲]

A drop of spectroscopy

Poster (2008, May)

A drop of spectroscopy

in Physicalia Magazine (2008), 30(3), 161-168

When a low viscosity oil droplet is laid onto the surface ofa high viscosity oil liquid, it stays at rest for a moment before coalescence. The coalescence can be delayed and sometimes inlibited by ... [more ▼]

When a low viscosity oil droplet is laid onto the surface ofa high viscosity oil liquid, it stays at rest for a moment before coalescence. The coalescence can be delayed and sometimes inlibited by injecting fresh air under the droplet. This can happen when the surface ofthe bath oscillates vertically. In this case the droplet basically bounces on the interface. We obsewe that the conditions for bouncing depends on the frequency, more precisely we observe resonance when the eigenfrequency of the droplet is excited. In some conditions, a droplet presents a non axi- symmetric mode of deformation. That leads to a rotation of the droplet and to a horizontal displacement. [less ▲]

Energetic approach for the characterization of taps in granular compaction

in Europhysics Letters [=EPL] (2008), 84(4),

We report numerical investigations for the compaction dynamics of dense granular assemblies. The studies are based on the non-smooth contact dynamics model. Our work suggests that the dimensionless ... [more ▼]

We report numerical investigations for the compaction dynamics of dense granular assemblies. The studies are based on the non-smooth contact dynamics model. Our work suggests that the dimensionless acceleration parameter Gamma, used by a large majortiy of authors, is not appropriate for rescaling the data. We prove that the dimensionless energy Xi, injected in the granular system at lift-off, is more appropriate and leads to robust interpretations of the compaction dynamics. Indeed, the injected energy allows to pass energy barriers that separate local equilibrium states. Using the Eyring picture of relaxation dynamic, we show that the consideration of Xi leads to a new law for compaction. [less ▲]