Viscous fingering is a commonly observed interfacial instability during fluid displacement, where fingerlike shape formed at the interface when more viscous displaced by less fluid. In this study, hybrid numerical model based on lattice Boltzmann method and finite difference developed for investigating control of leaky dielectric fluids confined in channel using electrohydrodynamics. Extensive ...

Self organization of large-scale structures in nature - either coherent structures like crystals, or incoherent dynamic structures like clouds - is governed by long-range interactions. In many problems, hydrodynamics and electrostatics are the source of such long-range interactions. The tuning of electrostatic interactions has helped to elucidate when coherent crystalline structures or incohere...

This study demonstrates for the first time abnormal electro-optic (EO) characteristics induced by electrohydrodynamics (EHD) in a polymer-dispersed liquid crystal (PDLC) film in the presence of a low-frequency (1 kHz) AC voltage. Large LC droplets (20−40 μm) buried in the film can be obtained after the illumination of one UV light with a weak intensity (~0.96 mW/cm2) for 12 h. This film exhibit...

The theoretical performance of a planar microscale ion generation device is analyzed using the direct simulation Monte Carlo (DSMC) technique. The discrete motion and interactions of electrons and ions are modeled for atmospheric air as represented by N2 and O2. The ionization threshold of the device in air is found to be 70 V because of the effects of molecular excitations that reduce the ener...

We discuss the seminal article in which Le Bellac and Lévy-Leblond have identified two Galilean limits of electromagnetism [1], and its modern implications. We use their results to point out some confusion in the literature and in the teaching of special relativity and electromagnetism. For instance, it is not widely recognized that there exist two well defined non-relativistic limits, so that ...

Nearly all research in micro- and nanofabrication focuses on the formation of solid structures of materials that perform some mechanical, electrical, optical, or related function. Fabricating patterns of charges, by contrast, is a much less well explored area that is of separate and growing interesting because the associated electric fields can be exploited to control the behavior of nanoscale ...

Microfluidic flow based multiplexed devices have gained significant promise in detecting biomarkers in complex biological samples. However, to fully exploit their use in bioanalysis, issues such as (i) low sensitivity and (ii) high levels of nonspecific adsorption of non-target species have to be overcome. Herein, we describe a new multiplexed device for the sensitive detection of multiple prot...

Horizontal and vertical liquid bridges are simple and powerful tools for exploring the interaction of high intensity electric fields (8-20 kV/cm) and polar dielectric liquids. These bridges are unique from capillary bridges in that they exhibit extensibility beyond a few millimeters, have complex bi-directional mass transfer patterns, and emit non-Planck infrared radiation. A number of common s...

Fractures provide pathways for fluids and solutes through crystalline rocks low permeability materials, thus playing a key role in many subsurface processes applications. In small aperture fractures, solute transport is strongly impacted by the coupling of electrical double layers at mineral–fluid interfaces to bulk ion transport. Yet, most models flow fractures ignore these effects. Solving su...

Planar microscale ionization devices that operate in atmospheric air have been developed out of highly graphitic polycrystalline diamond (HGPD). The devices have been fabricated on both silicon and quartz substrates with electrode gaps ranging from 5 to 20 m. Experiments show that the HGPD devices operate in the pre-breakdown regime where a field emission mode enables appreciable ionization cu...