A theoretical and experimental investigation of a magneto hydrodynamic stirrer is presented. Such a stirrer can be used to enhance mixing in micro total analysis systems. The stirrer utilizes arrays of electrodes deposited on a conduit's walls. The conduit is filled with an electrolyte solution. By applying alternating potential differences across pairs of electrodes, currents are induced in va...

Electromagnetic stirring is widely used in continuous casting of steel as a means to improve homogeneity of cast slabs. Industrial experience has shown that stirrer design and operating conditions have a strong influence on the metallurgical quality of the cast slab. This paper examines the effect of the stirrer current and field frequency on the flow in horizontal EMS of steel slabs. A threedi...

In Microbial Fuel Cells (MFCs), a mass transfer impact might be larger than expected because it not only effects the mass transfer losses (substrate flux [1, 2] and removal of waste [2]), but also effects the activation losses (mediator [3-5]) and the ohmic losses (proton transfer [6]). However, the convection/diffusion of the reactant transport from the bulk (reactant transport), which can be ...

The extraction device used in rotating-disk sorptive extraction consists of a Teflon disk in which a sorptive phase is fixed on one of its surfaces. Depending on the configuration, the rotation axis of the disk device can be either perpendicular or parallel to its radius, giving rise to two different mass transfer patterns when rotating-disk sorptive extraction is applied in liquid samples. In ...

Paramagnetic colloidal particles dispersed in water and deposited above magnetic bubble domains of a uniaxial ferrimagnetic garnet film are used as microscopic stirrer when subjected to external rotating magnetic fields. The hydrodynamic flow field above the stirrer is detected by tracking of nonmagnetic microspheres. The vorticity of the flow falls off inversely proportionally to the distance ...

Gábor Halász, Balázs Gyüre, Imre M. Jánosi, K. Gábor Szabó, and Tamás Tél von Kármán Laboratory for Environmental Flows, Eötvös University, Pázmány P. s. 1/A, H-1117 Budapest, Hungary Department of Fluid Mechanics, Budapest University of Technology, H-1111, Bertalan L. u. 4–6, Budapest, Hungary and Previous address: HAS Research Group for Theoretical Physics, H-1518, P.O. Box 32, Budapest, Hung...

A magneto-hydrodynamic (MHD) stirrer that exhibits chaotic advection is designed, modeled, and tested. The stirrer can operate as a stand-alone component or it can be incorporated into a MHD-controlled network. The stirrer consists of a conduit equipped with individually controlled electrodes positioned along its opposing walls. The conduit is filled with an electrolyte solution and positioned ...

It is well established that the bulk etch rates for solid state nuclear track detectors are a ected by the concentration and the temperature of the etchant. Recently, we found that the bulk etch rate for the LR 115 detector to be a ected by stirring during etching. In the present work, the e ects of stirring on the bulk etch rate of the CR-39 detector is investigated. One set of sample was etch...