Magnetoviscosity of a ferrofluid in an oscillating field.

B. U. Felderhof

Institut für Theoretische Physik A R.W.T.H. Aachen Templergraben 55, 52056 Aachen, Germany

Abstract
The magnetoviscosity of a ferrofluid flowing down a circular tube in the presence of an oscillating magnetic field in the direction of the axis is studied on the basis of hydrodynamics, and a relaxation equation for the magnetization. The proper treatment of collective interactions via the Maxwell field leads to a value for the magnetoviscosity different from that proposed by Shliomis \etal, except in the limit of zero frequency or in the dilute limit. Figs 1, Refs 15.