International Journal of Mathematics and Mathematical Sciences
Volume 2012 (2012), Article ID 641738, 15 pages
Research Article

An Analytic Study of the Reversal of Hartmann Flows by Rotating Magnetic Fields

Departamento de Análisis Matemático, Universidad de Valladolid, 47005 Valladolid, Spain

Received 20 March 2012; Accepted 9 July 2012

Academic Editor: Marco Squassina

Copyright © 2012 Manuel Núñez. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The effects of a background uniform rotating magnetic field acting in a conducting fluid with a parallel flow are studied analytically. The stationary version with a transversal magnetic field is well known as generating Hartmann boundary layers. The Lorentz force includes now one term depending on the rotation speed and the distance to the boundary wall. As one intuitively expects, the rotation of magnetic field lines pushes backwards or forwards the flow. One consequence is that near the wall the flow will eventually reverse its direction, provided the rate of rotation and/or the magnetic field are large enough. The configuration could also describe a fixed magnetic field and a rotating flow.