Analysis of droplet formation in microfluidic systems is important to understand the operation of these devices, and to permit optimal design and process control. Droplet formation in microfluidic Tjunction devices was studied using experimental and numerical methods. The simulations agree well with experimental data from PDMS devices; they show that droplet pinch-off is controlled not by visco...

Splashing is a phenomenon often observed during liquid droplet impact onto a solid surface. The threshold of splashing is known to be related to droplet size, impact velocity, and physical properties of the liquid, but the mechanisms that initiate splashing are not understood completely. In accordance with the Kelvin-Helmholtz (K-H) instability analysis, recent studies have shown that ambient g...

We evaluate the feasibility of manipulating droplets in two dimensions by exploiting Coulombic forces acting on conductive droplets immersed in a dielectric fluid. When a droplet suspended in an immiscible fluid is located near an electrode under a dc voltage, the droplet can be charged by direct contact, by charge transfer along an electrically conducting path, or by both mechanisms. This proc...

Electrowetting (EW)-induced droplet motion has been studied over the last decade in view of its promising applications in the field of microfluidics. The objective of the present work is to analyze the physics underlying two specific EW-based applications for microelectronics thermal management. The first of these involves heat absorption by liquid droplets moving on the surface of a chip under...

Dash, Susmita. Ph.D., Purdue University, December 2014. Droplet Behavior on Superhydrophobic Surfaces: Interfaces, Interactions, and Transport. Major Professor: Suresh V. Garimella, School of Mechanical Engineering. The primary objective of the present work is to study droplet dynamics on smooth hydrophobic and textured superhydrophobic surfaces, and to understand the dependence of interfacial ...

Seipin is necessary for both adipogenesis and lipid droplet (LD) organization in nonadipose tissues; however, its molecular function is incompletely understood. Phenotypes in the seipin-null mutant of Saccharomyces cerevisiae include aberrant droplet morphology (endoplasmic reticulum-droplet clusters and size heterogeneity) and sensitivity of droplet size to changes in phospholipid synthesis. I...

in this paper, the turbulent air droplet flow inside a single passage of a curved type vane separator has been studied numerically. the simulation is based on the eulerian - lagrangian method. for turbulent air flow calculations, a computer code was developed to solve the reynolds averaged navier stokes (rans) equations together with the equations of reynolds stress transport model (rstm) on co...

background: several multiphase flow analyses have been developed to predict the fate of particles used in inhalation drug delivery; however, the collapse of droplets during their passage through respiratory tract has not been investigated. objective: to assess the probability of droplet collapse in the upper respiratory tract. methods: a 3d model of mouth-to-second generation airway after the t...

The shape of microscopic fuel droplets may differ from the perfect sphere, affecting their external surface area and thus the heat transfer with the surrounding gas. Hence there is a need for the characterization of droplet shapes, and the estimation of external surface area, in order to enable the development of physically accurate mathematical models for the heating and evaporation of diesel ...

This paper describes the break-up of droplets in a concentrated emulsion during its flow as a 2D monolayer in a microchannel consisting of a narrow constriction. Analysis of the behavior of a large number of drops (N > 4000) shows that the number of break-ups increases with increasing flow rate, entrance angle to the constriction, and size of the drops relative to the width of the constriction....