Related papers: On a liquid drop "falling" inside a heavier miscib…
We present a comprehensive study of water drops sliding down chemically heterogeneous surfaces formed by a periodic pattern of alternating hydrophobic and hydrophilic stripes. Drops are found to undergo a stick-slip motion whose average…
Interfaces with a liquid are governing several phenomena. For instance, these interfaces are giving the shape of sessile droplets and rule the spread of liquids on surfaces. Here we analyze the shape of sessile axisymmetric drops and how it…
When a liquid drop falls on a solid substrate, the air layer in between them delays the occurrence of liquid--solid contact. For impacts on smooth substrates, the air film can even prevent wetting, allowing the drop to bounce off with…
The coalescence of liquid drops is a fundamental process that remains incompletely understood, particularly in the intermediate regimes where capillary, viscous, and inertial forces are comparable. Here, we experimentally investigate the…
We present a mesoscopic hydrodynamic model for a spreading drop of volatile partially wetting liquid on a solid porous layer of small thickness. Thereby, evaporation takes place under strong confinement, i.e., we consider a drop that…
Secondary droplets produced by interactions between falling fluid drops and a liquid pool play a significant role in engineering applications and geophysical processes in nature. This study uses direct numerical simulations to investigate…
The instability of a Fermi-liquid drop with respect to bulk density distortions is considered. It is shown that the presence of the surface strongly reduces the growth rate of the bulk instability of the finite Fermi-liquid drop because of…
Drops placed on a surface with a temperature above the Leidenfrost point float atop an evaporative vapor layer. In this fluid dynamics video, it is shown that for roughened surfaces the Leidenfrost point depends on the drop size, which runs…
The impact of a jet of droplets upon surfaces of varying hydrophobicity is studied via high-speed imaging. Microstructures on silicone surfaces consisting of cylindrical pillars of varying sizes and spacings are utilized to enhance…
We present results from an individual particle based model for the collision, coagulation and fragmentation of heavy drops moving in a turbulent flow. Such a model framework can help to bridge the gap between the full hydrodynamic…
Natural or industrial flows of a fluid often involve droplets or bubbles of another fluid, pinned by physical or chemical impurities or by the roughness of the bounding walls. Here we study numerically one drop pinned on a circular…
When a drop impacts a solid substrate or a thin liquid film, a thin gas disc is entrapped due to surface tension, the gas disc retracts into one or several bubbles. While the evolution of the gas disc for impact on solid substrate or film…
When placed upside down a liquid surface is known to destabilize above a certain size. However, vertical shaking can have a dynamical stabilizing effect. These oscillations can also make air bubbles sink in the liquid when created below a…
The coalescence of droplets plays a crucial role in nature and modern technology. Various experimental and theoretical studies explored droplet dynamics in 3D and on 2D solid or liquid substrates. In this paper, we demonstrate the…
We present an experimental and theoretical description of the kinetics of coalescence of two water drops on a plane solid surface. The case of partial wetting is considered. The drops are in an atmosphere of nitrogen saturated with water…
We numerically study the coalescence dynamics of two sessile droplets with radii $R_0$. The droplets are placed on top of a rigid substrate with a contact angle of $\theta_{eq.} = \pi/9$. Having a highly wettable substrate ($\theta_{eq} \ll…
The interface formation model is applied to describe the initial stages of the coalescence of two liquid drops in the presence of a viscous ambient fluid whose dynamics is fully accounted for. Our focus is on understanding (a) how this…
We show that a volatile liquid drop placed at the surface of a non-volatile liquid pool warmer than the boiling point of the drop can experience a Leidenfrost effect even for vanishingly small superheats. Such an observation points to the…
The interplay between thin film hydrodynamics and solidification produces formidably intricate geophysical structures, such as stalactites and icicles, whose shape is a testimony of their long growth. In simpler settings, liquid films can…
Large Leidenfrost drops exhibit erratic bubble bursts to release vapor accumulated beneath the liquid, becoming amorphous and unstable. Here we report an original and remarkably simple method to stabilize and design a Leidenfrost puddle.…