Effect of a magnetic field relaxation on the splash of ultrasonic absorption coefficient in magnetic nanofluid EMG – 605

 

I. E. Ovchinnikov

Moscow State University of Instrument Engineering and Computer Sciences

 

The paper is received on January 16, 2014

Abstract: The theoretical analysis was made on the experimental data for the ultrasonic velocity and absorption coefficient in water-based magnetic nanofluid EMG – 605 when exposed to a homogeneous static magnetic field with a magnitude from a few and up to 120 kA/m. It was shown, that the ultrasonic absorption coefficient splash can be explained by a process of relaxation of the magnetic field to its equilibrium value in a magnetic fluid. For magnetic fields from 30 kA/m and up to 120 kA/m the theoretical dependence is confirmed: the magnetoelasticity parameter is inversely proportional to the differential magnetic susceptibility.

Keywords: magnetic nanofluid, magnetic nanoparticles, magnetite, magnetic field, ultrasonics.