https://doi.org/10.1007/s100510070066
Magnetic permeability of a diphasic flow, made of liquid gallium and iron beads
1
Laboratoire de PhysiqueCNRS UMR 5672, École Normale Supérieure,
46 Allée d'Italie, 68007 Lyon, France
2
Laboratoire de Physique StatistiqueCNRS UMR 8550,
École Normale Supérieure, 24 rue Lhomond, 75005 Paris, France
Received:
6
March
2000
Revised:
13
July
2000
Published online: 15 November 2000
Magnetohydrodynamics studies in laboratory experiments have long
been restricted to low magnetic Reynolds number flows, mainly as a
result of the very high magnetic diffusivity 
of common conducting fluids (μ is the fluid's
magnetic permeability and σ its electrical conductivity).
The best conductivities are found in liquid metals which have a
unit magnetic permeability, relative to vacuum. We show
experimentally that a suspension of
solid particles with a high magnetic permeability in a liquid metal
yields an effective medium that has a high electrical conductivity and an
enhanced magnetic permeability. The dispersion of
the beads results from the turbulent fluid motion.
The range of accessible magnetic Reynolds number can be increased
by a factor of as much as 4 in our experimental setup.
PACS: 47.65.+a – Magnetohydrodynamics and electrohydrodynamics / 75.50.Mm – Magnetic liquids / 47.55.Kf – Multiphase and particle-laden flows
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2000
