Finite element numerical simulations were carried out in 2D geometries to map the magnetic field and force distribution produced by rectangular permanent magnets as a function of their size and position with respect to a microchannel. A single magnet, two magnets placed in attraction and in repulsion have been considered. The goal of this work is to show where magnetic beads are preferentially ...

Viscoelastic fluid flow-induced cross-streamline migration has recently received considerable attention because this process provides simple focusing and alignment over a wide range of flow rates. The lateral migration of particles depends on the channel geometry and physicochemical properties of particles. In this study, digital in-line holographic microscopy (DIHM) is employed to investigate ...

Two dimensional lubrication approximation is applied to the analysis of fluid flow in a rectangular microchannel with structured roughness. Each of two major walls is composed of designed microscale transverse ribs, modeled by twodimensional functions. A pressure drop correlation is formed as a direct function of these surface equations and the resultant velocity profile is incorporated into bo...

Flow characteristics of water were tested in a rectangular microchannel for Reynolds number (Re) between 0 and 446 by terahertz time domain spectroscopy (THz-TDS). Output THz peak trough intensities and the calculated absorbances of the flow were analyzed theoretically. The results show a rapid change for Re < 250 and a slow change as Re increases, which is caused by the early transition from l...

Study of thermo-hydraulic characteristics a novel microchannel heat sink having flow disrupting pins is numerically and experimentally carried out in this paper. Cylindrical are inserted from top cover into the rectangular instead conventional technique pin-fins originating base microchannel. Initially, effect pin diameter on performance studied optimum established, later enhanced (PE-MCHS) com...

Here we map gas-liquid two-phase flow regimes observed in polymeric microchannels with different wetting properties. We utilized video and confocal microscopy to examine two-phase flow patterns produced by parallel injection of air and water through a Y-shaped junction into a rectangular microchannel made of poly(dimethylsiloxane) (PDMS). We observed seven flow regimes in microchannels with hyd...

In this study, we described the fabrication method for microfluidic channels with circular-cross sectional geometries by reflow phenomenon. The photoresist reflow leads to shape change from rectangular to semicircular, and we optimized the reflow conditions by using positive photoresist to form the perfect cylindrical micropatterns. The resultant circular micropattern was used as a template for...