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.