Related papers: Microdroplets nucleation by dissolution of a multi…
For an immiscible oil drop immersed in a stably stratified ethanol-water mixture, a downwards solutal Marangoni flow is generated on the surface of the drop, owing to the concentration gradient, and the resulting propulsion competes against…
Solvent exchange is a process involving mixing between a good solvent with dissolved solute and a poor solvent. The process creates local oversaturation which causes the nucleation of minute solute droplets. Such ternary systems on a…
Microscopic active droplets are able to swim autonomously in viscous flows: this puzzling feature stems from solute exchanges with the surrounding fluid via surface reactions or their spontaneous solubilisation, and the interfacial flows…
We delineate and examine the distinct breakup modes of evaporating water-in-oil emulsion droplets under acoustic levitation. The emulsion droplets consist of decane/dodecane/tetradecane as oil, while the water concentration is varied from…
Chemotaxis and auto-chemotaxis play an important role in many essential biological processes. We present a self-propelling artificial swimmer system which exhibits chemotaxis as well as negative auto-chemotaxis. Oil droplets in an aqueous…
The lifetime $\tau$ of an isothermal and purely diffusively dissolving droplet in a host liquid scales as $\tau \sim R_0^2$ with its initial radius $R_0$ [Langmuir, Phys. Rev. 12, 368 (1919)]. For a droplet dissolving due to natural…
Small water droplets or particles located at an oil meniscus typically climb the meniscus due to unbalanced capillary forces. Here, we introduce a size-dependent reversal of this meniscus-climbing behavior, where upon cooling of the…
Water-in-oil emulsions and droplets exhibit completely different physico-chemical properties compared to oil-in-water emulsions and droplets. Thus, directly applying a standard theoretical model to water-in-oil systems cannot describe these…
Water in oil emulsions have a wide range of applications from chemical technology to microfluidics, where the stability of water droplets is of paramount importance. Here using an accessible and easily reproducible experimental setup we…
The multiphase flow of droplets is widespread, both at the industrial and the microscale, for both biological and non-biological applications alike. But the ensemble interactions of such systems are inherently nonlinear and complex,…
It is demonstrated that non-coalescent droplets of acetone can be formed on liquid substrates. The fluid flows around and in an acetone droplet hovering on water are recorded to shed light on the mechanisms which might lead to…
The wetting properties of multi-component liquids are crucial to numerous industrial applications. The mechanisms that determine the contact angles for such liquids remain poorly understood, with many intricacies arising due to complex…
Solvent shifting is a process in which a non-solvent is added to a solvent/solute mixture and extracts the solvent. The solvent and the non-solvent are miscible. Because of solution supersaturation a portion of the solute transforms to…
The combustion characteristics of ethanol/Jet A-1 fuel droplets having three different proportions of ethanol (10%, 30%, and 50% by vol.) are investigated in the present study. The large volatility differential between ethanol and Jet A-1…
The transport and aggregation of particles in suspensions is an important process in many physicochemical and industrial processes. In this work, we study the transport of particles in an evaporating binary droplet. Surprisingly, the…
The Greek aperitif Ouzo is not only famous for its specific anise-flavored taste, but also for its ability to turn from a transparent miscible liquid to a milky-white colored emulsion when water is added. Recently, it has been shown that…
Atomization of emulsion droplets is ubiquitous across a variety of application domains ranging from NextGen combustors to fabrication of biomedical implants. An understanding of the atomization mechanism in emulsions can result in a…
An alcohol (pentanol) droplet exhibits spontaneous agitation on an aqueous solution, driven by a solutal Marangoni effect. We found that the droplet's mode of motion is controlled by its volume. A droplet with a volume of less than $0.1…
The Marangoni effect refers to fluid flow induced by a gradient in surface tension at a fluid-fluid interface. We determine the full three-dimensional Marangoni flow generated by a non-uniform surface tension profile at the interface of a…
Emulsion fuels have the potential to reduce both particulate matter and NOx emissions and can potentially improve the efficiency of combustion engines. However, their limited stability remains a critical barrier to practical use as an…