Viscosity magnetic fluid

Papell, S.S.Low viscosity magnetic fluid obtained by the colloidal suspension of magnetic particles. US Patent (1965) 3,215,572. 

D. Antisymmetric Stresses, Internal Spin Fields, and Vortex Viscosity in Magnetic Fluids... 

These suspension viscosity concepts are of growing technological importance in rationalizing and quantifying the behavior and properties of so-called magnetic fluids (Rosensweig, 1982, 1985, 1987). In a novel proposal, Brenner (1984) outlined a potentially useful scheme to use the apparently rigid-body rotation of a dipolar suspension to measure its vortex viscosity... 

Magnetic fluids can be used as a high-density solution for the sink-and-float separation of solids in suspension. This separation technique for non-ferrous metals is based on the anomalous viscosity increase of a magnetic suspension as a function of applied field. The magnetic fluid consists typically of magnetite particles with an average diameter of 100 A in water, with 15-25 wt% of ferrite. To prevent particle aggregation, a surfactant such as kerosene and oleic acid, or a polymer is usually... 

Fig. 5.26. Dependence of the viscosity of a magnetic fluid on the applied field the volume concentration of magnetic particles is indicated (in vol%) (Tsutaoka et al, 1989).

VISCOSITY OF MAGNETIC FLUID IN A MAGNETIC FIELD. ROSENSWEIG R E KAISER R MISKOLCZY G J COLLOID INTERFACE SCI... 

The viscosity of colloids is influenced by temperature, interactions between particles, concentration, shape and dimension of the particles and viscosity of the carrier hquid. Owing to the complex phenomena, there is no general formula for the viscosity of suspensions, in particular for magnetic fluids, but various approximating... 

A thorough analysis [16, 17, 18, 25] of the hydrodynamic volumic fraction ( h) dependence of the viscosity ri) of mono-layer and double-layer sterically stabilized magnetic fluids of high colloidal stability evidenced that this is best described by the theoretical formula obtained by Chow [27] ... 

Fig. 5 Shear-rate dependence of the viscosity of pentanol-based magnetic fluids of different saturation magnetization magnetic fluid/pentanol (sample 10) (circles) magnetic fluid/pentanol (sample 9) (triangles) magnetic fluid/pentanol (sample 8) (squares)... 

The creation terms embody the changes in momentum arising from external forces in accordance with Newton s second law (F = ma). The body forces arise from gravitational, electrostatic, and magnetic fields. The surface forces are the shear and normal forces acting on the fluid diffusion of momentum, as manifested in viscosity, is included in these terms. In practice the vector equation is usually resolved into its Cartesian components and the normal stresses are set equal to the pressures over those surfaces through which fluid is flowing. 

H = magnetic-field intensity dB/dz = magnetic-field gradient T = fluid viscosity b = particle diameter... 

A. G., Goloshevsky, J. H. Walton, M. V. Shutov, J. S. de Ropp, S. D. Collins, M. J. McCarthy 2005, (Nuclear magnetic resonance imaging for viscosity measurements of non-Newtonian fluids using a miniaturized rf coil), Meas. Sci. Technol. 16, 513-518. 

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