When a droplet hits a hot surface beyond the Leidenfrost temperature, the droplet will bounce on the hot surface. This unique bouncing phenomenon only occurs in the film boiling region. This paper discusses the relationship between the residence time of droplet and droplet bouncing phenomena during droplet impact on hot horizontal surfaces. In this experiment, aluminum (mirror polished) was sel...

We report experiments and detailed numerical modeling of mixtures of primary reference fuel (PRF) droplets consisting of n -heptane and iso -octane with initial droplet diameters of 0.5 and 3.51 mm. The results show a quasi-steady, low temperature (or “Cool Flame” ( CF )) droplet burning mode that stems from a varying two-stage chemical kinetic behavior of the combustion chemistry. The simulati...

Droplet-based transport phenomena driven by surface tension have been explored as an automated pumping source for a number of chemical and biological applications. In this paper, we present a comprehensive theoretical and experimental investigation of unconventional droplet-based motions on a superhydrophobic-patterned surface microfluidic (S(2)M) platform. The S(2)M surfaces are monolithically...

In many electrowetting on dielectric (EWOD) based microfluidics devices, droplet actuation speed is a crucial performance-controlling parameter. Our present study aims to characterize and study droplet speed in a typical EWOD device. First, a practical droplet speed measurement method has been methodically demonstrated and some related velocity terms have been introduced. Next, influence of ele...

In vitro aged sheep erythrocytes and sheep erythrocyte ghosts spontaneously release vesicles that consist of long protrusions affixed to flattened headlike structures. The intramembranous particles seen on the protoplasmic face of freeze fracture electron micrographs of vesicle protrusions are arranged in paired particle rows. On the equivalent fracture face of headlike structures, the particle...

We present a droplet microfluidic method to extract molecules of interest from a droplet in a rapid and continuous fashion. We accomplish this by first marginalizing functionalized super-paramagnetic beads within the droplet using a magnetic field, and then splitting the droplet into one droplet containing the majority of magnetic beads and one droplet containing the minority fraction. We quant...

We used the lattice Boltzmann method to study the displacement of a two-dimensional immiscible droplet subject to gravitational forces in a channel. The dynamic behavior of the droplet is shown, and the effects of the contact angle, Bond number ~the ratio of gravitational to surface forces!, droplet size, and density and viscosity ratios of the droplet to the displacing fluid are investigated. ...

Here we show that dielectrophoretic (DEP) liquid actuation can be used to dispense arrays of nanoliter-sized droplets loaded with biomolecules. Size-based enrichment of these biomolecules occurs rapidly and simultaneously with the droplet dispensing. The physical mechanism responsible for the effect is the positive DEP force directed toward the electrodes that is imposed by the non-uniform elec...

−Stable hydrocarbon oil (hexadecane, C16)/nonionic surfactant (HCO-60, Span 80)/water system oil-inwater nanoemulsions were prepared by the phase inversion composition method at elevated temperature. To minimize droplet size, the composition ratio for stable nanoemulsions, we experimented by changing the HLB value, oil/surfactant ratio, and droplet volume fraction. When the HLBmix value 11, the...

The droplet size can influence the application of a spray system. We apply grey theory in establishing a model of forecasting droplet size. The example used in this study shows that this method is precise in forecasting the droplet size, and is helpful to choose the other parameters of a spray system within a certain droplet size.