Departmental Papers (MEAM)

Document Type

Journal Article

Date of this Version

October 2001


Postprint version. Published in Sensors and Actuators B: Chemical, Volume 79, Issues 2-3, October 2001, pages 207-215.
Publisher URL:


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 various directions in the solution. In the presence of a magnetic field, the coupling between the magnetic and electric fields induces body (Lorentz) forces in the fluid. Since the electrodes can be patterned in various ways, fairly complex flow fields can be generated. In particular, in this paper, we describe the induction of cellular motion. This motion can be used to deform and stretch material interfaces and to enhance mixing. The MHD stirrer does not utilize any moving parts. The experimental observations are in good agreement with theoretical predictions.


minute stirrer, micro mixer, magneto hydro dynamics, MHD



Date Posted: 27 November 2007

This document has been peer reviewed.