Magnetorheological (MR) fluids are a type of smart material whose effective viscosity may be rapidly changed (~few ms) in a nearly reversible manner by the application and removal of an externally-applied magnetic field. Conventional MR fluids are composed of micron-scale, ferromagnetic spherical particles (typically 30 to 40 volume percent) suspended in a hydrocarbon, silicone, or aqueous carr...

Electroand magnetorheological fluids are smart, synthetic fluids changing their viscosity from liquid to semisolid state within milliseconds if a sufficiently strong electric or magnetic field is applied. When used in suitable devices, they offer the innovative potential of very fast, adaptively controllable interfaces between mechanical devices and electronic control units. This paper gives an...

Magnetic nanofluids (known also as ferrofluids or magnetic fluids) are a special category of smart nanomaterials, in particular magnetically controllable nanofluids [1]. These types of nanofluids are colloids of magnetic nanoparticles, such as Fe3O4, γ-Fe2O3, CoFe2O4, Co, Fe or Fe-C, stably dispersed in a carrier liquid [2]. Consequently, these nanomaterials manifest simultaneously fluid and ma...

The ferrofluid dynamics theory is applied to thermodiffusive problems in magnetic fluids in the presence of magnetic fields. The analytical form for the magnetic part of the chemical potential and the most general expression of the mass flux are given. By applying these results to experiments, global Soret coefficients in agreement with measurements are determined. An estimate for a hitherto un...

The first direct measurements of effective magnetic diffusivity in turbulent flow of electroconductive fluids (the so-called β effect) under the magnetic Reynolds number Rm≫1 are reported. The measurements are performed in a nonstationary turbulent flow of liquid sodium, generated in a closed toroidal channel. The peak level of the Reynolds number reached Re≈3×10(6), which corresponds to the ma...

This paper proposes a needle-type giant magnetoresistance (GMR) sensor for very low magnetic fluid weight density of ferrofluid estimation. The magnetic fluids or ferrofluids due to their biocompatibility are used for various applications in medicine such as cancer treatment, magnetic resonance imagining (MRI), cell separation and also to detect the bacteria. The high sensitivity of GMR sensor ...

We have proposed a viscoelastic model of the Maxwell stresses due to the disorganized magnetic field in MRI-driven MHD turbulence. Viscoelastic fluids in the laboratory are known to produce jet-like structures under the action of a rotating sphere. Here we argue that a similar mechanism may help explain jets in protostellar systems. Such jets would be driven not by large-scale organized magneti...