Effect of a magnetic field relaxation on the sound velocity in magnetic
fluid
I. E. Ovchinnikov
Moscow State University of Instrument Engineering
and Computer Sciences
Received
April 24, 2013
Abstract: The propagation of
hydrodynamic waves in magnetic fluid was considered in linear approximation
with taking into account the process of relaxation of the magnetic field to
its equilibrium value. The expressions for phase velocities and absorption
coefficients were obtained for the Alfven type wave, the fast and slow magnetohydrodinamic
waves. It was shown the calculated values to be in a quantitative agreement
with experimental data on the ultrasonic velocity anisotropy in a water-based
magnetic fluid under prolonged exposure of the homogeneous static magnetic
field.
Key words: magnetic fluid, magnetic
field, ultrasonics, nanoparticles, magnetite.