The Ohta-Kawasaki density functional theory of diblock copolymers gives rise to a nonlocal free boundary problem. In a proper range of the block composition parameter and the nonlocal interaction parameter, an equilibrium pattern of many droplets exists in a general planar domain. A sub-range of the parameters is identified where the multiple droplet pattern is stable. This stable droplet patte...

Droplet formation in the presence of nanoparticles was studied in a T-shaped microfluidic device numerically. Nanoparticles in continuous phase did not influence droplet formation dynamics obviously. Contrarily, the presence of nanoparticles in dispersed phase will influence evidently droplet formation dynamics, likely reasons are the accumulation of nanoparticles at the liquid-liquid interface...

Abstract Impact spreading of droplets in spray coating of paper was investigated using numerical simulation based on a volume-offluid (VOF) model. The results include the effects of droplet size, droplet impact velocity, liquid viscosity, liquid surface tension and paper web velocity on droplet spreading. Pressure and strain rate fields as well as timescales of spreading are reported. The resul...

Dynamics of two droplets interactions on a substrate (droplet impact on a sessile droplet) are numerically investigated using OpenFOAM. The impact speed, location of the impacting droplet, viscosity and surface tension were varied in the numerical studies. We found that when the surface tension dominates the flow, the mass canter of two droplets moves to impacting droplet side. When the inertia...

With the broad interest in and development of superhydrophobic surfaces for self-cleaning, condensation heat transfer enhancement and anti-icing applications, more detailed insights on droplet interactions on these surfaces have emerged. Specifically, when two droplets coalesce, they can spontaneously jump away from a superhydrophobic surface due to the release of excess surface energy. Here we...

A new mathematical treatment of the problem of droplet growth via diffusion of molecules from a supersaturated vapor is presented. The theory is based on a semiquantitative analysis with good physical arguments and is justified by its reasonable predictions. For example it recovers the time honored growth law in which, to a high degree of approximation, the droplet radius increases with the squ...

Abstract A mathematical model for the quasi-steady evaporation of a thin liquid droplet on a thin substrate that incorporates the dependence of the saturation concentration of vapour at the free surface of the droplet on temperature is used to examine an atypical situation in which the substrate has a high thermal resistance relative to the droplet (i.e. it is highly insulating and/or is thick ...

This paper aims to investigate a mechanism of microdroplet formation at a micro T-shaped junction using a “phaselocked multicolor confocal micro-PIV (Particle Image Velocimetry)” technique[1]. The multicolor system can measure dynamic behavior of each phase of multiphase flow separately and simultaneously. Additionally, the phase-locking technique enables picking up same condition of droplet fo...

The dynamics of droplet spreading on two-dimensional wicking surfaces were studied using square arrays of Si nanopillars. It was observed that the wicking film always precedes the droplet edge during the spreading process causing the droplet to effectively spread on a Cassie-Baxter surface composed of solid and liquid phases. Unlike the continual spreading of the wicking film, however, the drop...

Lipid droplets, the intracellular storage organelles for neutral lipids, exist in a wide range of sizes and of morphologically distinct organization, from loosely dispersed lipid droplets to tightly packed lipid droplet clusters. We show that the lipid droplet protein AUP1 induces cluster formation. A fraction of AUP1 is monoubiquitinated at various lysine residues. This process depends on its ...