MAGNETODYNAMICS OF A DILUTE FERROCOLLOID IN A SHEAR FLOW

Abstract

The work is devoted to a theoretical study of a dilute suspension of magnetic nanoparticles under the combined action of a simple shear flow and a constant magnetic field. The main attention is paid to the dynamics of the magnetization vector of the system. It is shown that at any nonzero temperature the magnetization takes a stationary orientation in a finite time. The direction of magnetization generally does not coincide with the direction of the field. Equilibrium and non-equilibrium magnetization components are calculated as functions of two dimensionless parameters – Mason number (i.e., ratio of hydrodynamic torque to magnetic) and Peclet number (i. e., ratio of hydrodynamic moment to thermal).