The current theory of alternating-current electro-osmosis (ACEO) is unable to explain the experimentally observed flow reversal of planar ACEO pumps at high frequency (above the peak, typically 10-100 kHz), low salt concentration (1-1000 microM) , and moderate voltage (2-6 V), even taking into account Faradaic surface reactions, nonlinear double-layer capacitance, and bulk electrothermal flows....

The understanding of electrokinetic transport of fluid or particles in microchannel plays an important role in the design and the optimization of microand nanofluidic devices. Two important electrokinetic phenomena are electro-osmosis and electrophoresis. In order to study these phenomena, the lattice Boltzmann solver is coupled with the iteration solver for the Poisson equation. Using these nu...

The lateral intercellular spaces (LIS) are believed to be the final common pathway for fluid reabsorption from the renal proximal tubule. We postulate that electrogenic sodium pumps in the lateral membranes produce an electrical potential within the LIS, that the lateral membranes bear a net negative charge, and that fluid moves parallel to these membranes because of Helmholtz-type electro-osmo...

AC electro-osmotic (ACEO) pumps in microfluidics currently involve planar electrode arrays, but recent work on the underlying phenomenon of induced-charge electro-osmosis (ICEO) suggests that three-dimensional (3D) geometries may be exploited to achieve faster flows. In this paper, we present some new design principles for periodic 3D ACEO pumps, such as the "fluid conveyor belt" of ICEO flow o...

Recently, there has been a growing interest in using induced electro-osmosis to pump fluids in microfluidic devices. We show that induced electroosmosis can also be used to promote stirring and chaotic advection. To this end, we study theoretically a stirrer in which the flow patterns are alternated in time. We first analyze an idealized embodiment of the stirrer that admits a simple analytical...

Surface charge density and distribution dependence of a nanochannel electro-osmotic flow was examined using a molecular dynamics (MD) model. Systems consisting of Na and Cl− ions in water confined between crystalline walls with varying negative charge on inner surfaces in an external electric field were investigated. At low surface charge densities, water flows as expected by common interpretat...

Building on our recent work on induced-charge electro-osmosis (ICEO) and electrophoresis (ICEP), as well as the Russian literature on spherical metal colloids, we examine the rich consequences of broken geometric and field symmetries upon the ICEO flow around conducting bodies. Through a variety of paradigmatic examples involving ideally polarizable (e.g. metal) bodies with thin double layers i...