We studied the free fluid-fluid interface in a phase-separated colloid-polymer dispersion with laser scanning confocal microscopy and directly observed thermally induced capillary waves at the interface in real space. Experimental results for static and dynamic correlation functions validate the capillary wave model down to almost the particle level. The ultralow interfacial tension, the capill...

We present a programmable microfluidic static droplet array (SDA) device that can perform user-defined multistep combinatorial protocols. It combines the passive storage of aqueous droplets without any external control with integrated microvalves for discrete sample dispensing and dispersion-free unit operation. The addressable picoliter-volume reaction is systematically achieved by consecutive...

1. The transport dynamics of expiratory droplets was modelled and verified against experimental data. 2. Droplet size distributions in air were measured. Small droplets (initial size ≤45 μm) were largely airborne. Large droplets (initial size ≥87.5 μm) settled quickly. 3. The transport characteristics of expiratory droplets were highly influenced by ventilation airflow patterns. The location of...

high temperatures are often encountered in almost all of the combustion systems, therefore, thermal radiation heat transfer can influence the droplets heat up rate and consequently their life time. in this paper, the effect of thermal radiation heat transfer is investigated for two cases of directional and spherically symmetric illuminations. the flow and temperature fields insdie and outside o...

As a droplet moves, due to evaporation at the surface, the droplet size is gradually reduced. Due to decreasing the size of the droplets moving in the spray core, the surface charges become closer and the repulsive force between the charges increases. When the Coulombic force overcomes the surface tension force (Rayleigh instability) the droplet breaks into smaller droplets (Coulomb fission). T...

Effective radius re (defined as the ratio of the third to the second moment of a droplet size distribution) is one of the crucial variables that determine the radiative properties of liquid water clouds (Hansen and Travis 1974). The inclusion and parameterization of re in climate models has proven to be critical for assessing global climate change (Slingo 1990; Dandin et al. 1997). There has be...

a modified model has been analytically developed to describe the induction time of an elliptic air bubble in contact with an elliptic hydrophobic oil droplet. the role of hydrophobicity was revealed in the slippage of liquid over the surfaces of bubble and droplet. in this condition, the analytical relationships for pressure distribution and consequently hydrodynamic resistance force through th...

The increased concern about environmental effect of off-target deposits of pesticides use has resulted in the development of numerous spray drift models. Statistical models based on experimental field studies are used to estimate off-target deposits for different sprayers in various environmental conditions. Random-walk and computational fluid dynamics (CFD) models have been used to predict the...

Abstract In this paper interparticle potential model of the lattice Boltzmann method (LBM) is used to simulate deformation and breakup of a falling droplet under gravity force. First this model is applied to ensure that the surface tension effect is properly implemented in this model. Two tests have been considered. First, it has been checked an initial square drop in a 2D domain can freely def...

The development of a general theoretical framework for describing the behaviour of a crystal driven far from equilibrium has proved difficult. Microfluidic crystals, formed by the introduction of droplets of immiscible fluid into a liquid-filled channel, provide a convenient means to explore and develop models to describe non-equilibrium dynamics. Owing to the fact that these systems operate at...