A5008835439- Fluid Dynamics and Thin Films
- Nanomaterials and Printing Technologies
- Fluid Dynamics and Heat Transfer
- Surface Modification and Superhydrophobicity
- Nonlinear Dynamics and Pattern Formation
- Heat Transfer and Boiling Studies
- Fluid Dynamics and Turbulent Flows
- Phase Equilibria and Thermodynamics
- nanoparticles nucleation surface interactions
- Advanced Thermodynamics and Statistical Mechanics
- Solidification and crystal growth phenomena
- Adhesion, Friction, and Surface Interactions
- Electrohydrodynamics and Fluid Dynamics
- Spacecraft and Cryogenic Technologies
- Gas Dynamics and Kinetic Theory
- Particle Dynamics in Fluid Flows
- Heat Transfer and Optimization
- Fluid Dynamics and Mixing
- Innovative Microfluidic and Catalytic Techniques Innovation
- Carbon Dioxide Capture Technologies
- Pickering emulsions and particle stabilization
- Field-Flow Fractionation Techniques
- Nanofluid Flow and Heat Transfer
- Planetary Science and Exploration
- Geomagnetism and Paleomagnetism Studies
Université Libre de Bruxelles
2015-2024
Physique et Mécanique des Milieux Hétérogènes
2018
ESPCI Paris
2018
Université Paris Sciences et Lettres
2018
Université Paris Cité
2018
Sorbonne Université
2018
Centre National de la Recherche Scientifique
2018
Ecole d'Ingénieurs de PURPAN
2006
Russian Academy of Sciences
2003
Fund for Scientific Research
2001
A drop of water deposited on a cold plate freezes into an ice with pointy tip. While this phenomenon clearly finds its origin in the expansion upon freezing, quantitative description tip singularity has remained elusive. Here we demonstrate how geometry freezing front, determined by heat transfer considerations, is crucial for formation. We perform systematic measurements angles conical tip, and reveal dynamics solidification front Hele-Shaw geometry. It found that cone angle independent...
Adjusting the wetting properties of water through addition a miscible liquid is commonly used in wide variety industrial processes involving interfaces. We investigate experimentally evolution drop and volatile alcohol deposited on bath oil: The spreads spontaneously fragments into myriad minute droplets whose size strongly depends initial concentration alcohol. Marangoni flows induced by evaporation play key role overall phenomenon. intricate coupling hydrodynamics, wetting, well captured...
The local evaporation rate and interfacial temperature are two quintessential characteristics for the study of evaporating droplets. Here, it is shown how one can extract these quantities by measuring vapor concentration field around droplet with digital holographic interferometry. As a concrete example, an freely receding pending 3M Novec HFE-7000 analyzed at ambient conditions. measured cloud to deviate significantly from pure-diffusion regime calculation, but compares favorably new...
This publication lays the foundation for description of Multiscale Boiling Experiment, which was conducted within two measurement campaigns on International Space Station between 2019 and 2021. The experiment addresses fundamental questions about two-phase heat transfer during boiling processes. For this purpose, single or few subsequential bubbles are selectively ignited a heated substrate using short laser pulse. A detailed investigation phenomena is possible, as process temporally slowed...
We here present a simple fitting-parameter-free theory of the Leidenfrost effect (droplet levitation above superheated plate) covering full range stable shapes, i.e., from small quasispherical droplets to larger puddles floating on pocketlike vapor film. The geometry this film is found be in excellent quantitative agreement with interferometric measurements Burton et al. [Phys. Rev. Lett. 109, 074301 (2012)]. also obtain new scalings generalizing classical ones derived by Biance Fluids 15,...
Freely receding evaporating sessile droplets of perfectly wetting liquids, for which the observed finite contact angles are attributed to evaporation, studied with a Mach-Zehnder interferometer. The experimentally obtained droplet shapes found depart, under some conditions, from classical macroscopic static profile droplet. deviations (or absence thereof) explained in terms Marangoni flow due evaporation-induced thermal gradients along liquid-air interface. When such effect is strong,...
When a liquid droplet is placed on very hot solid, it levitates its own vapor layer, phenomenon called the Leidenfrost effect. Although mechanisms governing droplet's levitation have been explored, not much known about fate of droplet. Here we report final stages evaporation droplets. While initially small droplets tend to take off, unexpectedly, large ones explode with crack sound. We interpret these in context unavoidable contaminants, which accumulate at droplet-air interface, resulting...
The Benney equation including thermocapillary effects is considered to study a liquid film flowing down homogeneously heated inclined wall. link between the finite-time blow-up of and absence one-hump travelling-wave solution associated dynamical system accurately demonstrated in whole range linearly unstable wavenumbers. Then boundary tracked space parameters accounting for flow rate, surface tension, inclination thermocapillarity. In particular, latter two can strongly reduce validity...
The present theoretical study focuses on the dynamics of a thin liquid film falling down vertical plate with nonuniform, sinusoidal temperature distribution. results are compared to those obtained in case uniform governing evolution equation for thickness profile based long-wave theory accounts two instability mechanisms related thermocapillarity. first mechanism is due an inhomogeneity at liquid–gas interface induced by perturbations thickness, when heat transfer gas phase present, while...
The roughness of a solid is known to increase the minimal temperature for observing Leidenfrost effect. A new study shows that volatile liquid drop placed on surface smooth substrate---a non-volatile pool---reaches state as soon pool just hotter than boiling point, with no apparent threshold.
The extent of spreading molten drops onto a cold substrate depends on temperature. Experimental and theoretical results show strong evidence that the solidifying is arrested when liquid at contact line reaches critical temperature, which determined by effect kinetic undercooling.
Density variations induced by gas absorption in reactive aqueous solutions often trigger buoyancy-induced motions, generally the form of plumes monotonically sinking into bulk liquid and enhancing rate. Here, we contrast two types CO2-absorbing alkaline solutions, studying their dynamics inside a vertical Hele-Shaw cell interferometry. While first one indeed behaves as expected, second leads to quite unusual oscillatory (phase-slipping) convective plumes, which moreover does not lead...
When a liquid drop is placed on highly superheated surface, it can be levitated by its own vapour. This remarkable phenomenon referred to as the Leidenfrost effect. The thermally insulating vapour film results in severe reduction of heat transfer rate compared experiments at lower surface temperatures, where direct contact with solid surface. A commonly made assumption that this isothermal, which least questionable for materials low thermal conductivity, resulting an overestimation...
We study B\'enard-Marangoni instability in a system formed by horizontal liquid layer and its overlying vapor. The is lying on hot rigid plate the vapor bounded cold parallel plate. A pump maintains reduced pressure evacuates This investigation undertaken within classical quasisteady approximation for both phases. two layers are separated deformable interface. Temporarily frozen temperature velocity distributions employed at each instant stability analysis, limited to infinitesimal...
For a liquid advancing or receding on flat bare solid in vapor atmosphere, we show that no singularities fact arise at the contact (triple) line. Contrary to common expectations, this does not require any ``regularizing'' microscopic effect (such as slip substrate, disjoining pressure precursor films). The key here is Kelvin effect, i.e., curvature-induced variation of saturation conditions. Importantly, evaporation-related appear either. We proceed within lubrication approximation and...
The oscillating convective structures appearing at the threshold of two-layer Rayleigh–Bénard instability are analyzed in nonlinear regime. By deriving amplitude equations for left- and right-traveling waves from infinite Prandtl number Boussinesq equations, it is shown that one these should generally appear, rather than standing waves, sufficiently large cells. Numerical results show have a limited range existence, because hysteretic transition to stationary convection occurs when Rayleigh...