Electro-rheological fluids

Tao, R. (Ed.), Electro-Rheological Fluids and Magneto-Rheological Suspensions, World Scientific Publishing Co. Hackensack, NJ, 2000. 

Nakano M, KoyamaK (eds) (1997) Electro-rheological fluids, magneto-rheological suspensions and their applications. World Scientific, Hackensack, NJ... 

The actuators based on electro-rheological fluids are still at a very early stage of development. These fluids increase their viscosity under an electric field by means of a mechanism of spacial orientation of their molecular structure the resulting mass redistribution may change the vibrational properties of the host composite structure. Because available data on this technology is scarce, its real effectiveness is under discussion. 

F.E. Filisko, L.H. Radzilowski, An intrinsic mechanism for the activity of alumino-silicate based electrorheological materials, J. Rheol, 1990,34,539. H. Block, J.P. Kelly, Electro-rheological fluids, UK Patent 217051B, 1986. 

Liu J, Mou T, Zhu Y, Haddadian E, Lin X (1996) In Bullough WA (ed) Electro-Rheological Fluids, Magneto-Rheological Suspensions and Associated Technology. World Scientific, Singapore... 

Nikitczuk J, Weinberg B, and Mavroidis G, Control of electro-rheological fluid based resistive torque elements for use in active rehabilitation devices. Smart Materials and Structures, vol. 16, pp. 418-428,2007. 

Sianaki, A.H. BuUough, W.A. Tozer, R. Whittle, M. Experimental Investigation into Electrical Modelling of Electro-rheological Fluid Shear Mode. Proc. I.E.E, Sci. Meast. Tech. Vof 141, No. 6 (1994), pp. 531-537... 

Dwyer-Joyce, R. Bullough, W.A. Lingard, S. Elastohydrodynamic Performance of Unexcited Electro-Rheological Fluids. Proc 5th Int. Conf. ERF/MRS, held SMMART Sheffield. World Scientific (July 1995), pp. 376-384... 

Duclos, T.G. Design of Devices Using Electro-rheological Fluids. Soc. Auto. Engineers, SAE Paper 881134 (1988)... 

Mavroidis, C., Pfeiffer, C., Bar-Cohen, Y. Controlled compliance haptic interface using electro-rheological fluids. In Proceeding of SPIE, vol. 3987, pp. 300-310 (2000)... 

This transition from a homogeneous towards a nonhomogeneous flow has been reported in complex fluids of various microstructure such as lyotropic micellar and lamellar phases [44,121,122], triblock copolymers solutions [123,124], viral suspensions [125], thermotropic liquid crystal polymers [126], electro-rheological fluids [127], soft glassy materials [128], granular materials [129,130], or foams [131-133]. 

Recently there has been much interest in composites of magnetic particles in a soft matrix which respond to a magnetic field by a change of shape and properties [147]. These materials are the elastomeric equivalents of magneto-rheological fluids and electro-rheological fluids. 

Taylor, P.M., Pollet, D.M., Hosseini-Sianaki, A. and Varley, CJ. (1998) Advances in electro-rheological fluid based tactile array. Displays, 18, 135-41. 

Composites with filler concentrations close to the percolation threshold exhibit conductivity which is sensitive to compressive deformation, since this brings the metal particles into contact, thereby forming percolation pathways. This sensitivity has been exploited especially in anisotropic composites. These are made by prealigning the metal particles with either electric or magnetic fields. This alignment is identical with that produced by external fields in electro- and magneto-rheological fluids where at a critical field continuous threads of... 

Polyaniline filaments within the mesoporous channel host (aluminosilicate) have significant conductivity, and this demonstration of conjugated polymer with mobile charge carriers in nanometer channels represents a step toward the design of nanometer electronic devices. These composites have potential as stable molecular wires, which can be applied in the design of batteries and systems to accumulate electric charge. SBA-15 with polyaniline inside the pore channels was used as a dispersed phase in electro-rheological (ER) fluids. 

In this section, we discuss the behavior of liquid crystal suspensions under the action of an external electric field. The behavior of colloidal suspensions in electric fields is of considerable technological interest with the so-called Electro-Rheological (ER) fluids [17, 18]. The main features of this behavior are now rather well understood. When an external field is applied, particles suspended in an isotropic fluid become polarized. Resultant dipole-dipole interactions between the particles lead to their chaining along the direction of the applied field. When suspended in a liquid crystal host, colloidal particles are also expected to be polarized upon the application of an electric field. However, new phenomena may take place because of the specific response of the liquid crystal. In this case, the external field is likely to alter the distortions of the liquid crystal alignment... 

Abstract The physical properties, based on simulation results, of model fluids and solids bearing an electric or magnetic point dipole moment are described. Comparison is made with experimental data on ferrofluids and electro- or magneto-rheological fluids. The qualitative agreement between experiment and simulation shows the interest of these simple models for the comprehension of physical systems where the dipolar interaction dominates. 

Hosseini-SianaJd, A. Makin, J. Xiao, S. Johnson, A.R. Firoozian, R. Bullough, W.A. Operational Considerations in the Use of an Electro-Rheological Catch Device. Proc. Soc. Fluid Power Transmission and Control, 1st Fluid Power Trans. Control Symp., Beijing, Beijing Inst. Tech. (1991), pp. 591-595... 

Among the adaptive materials currently on the forefront are liquid crystals, electro- and magneto-rheological (ER/MR) fluids, thermo- and physioreponsive gels, and shape memory alloys. In all but the last case, these systems involve... 

Gavin H. P., The effect of particle concentration inhomogeneities on the steady flow of electro- and magneto-rheological materials. J. Non-Newton. Fluid Mech. 71 (1997)pp. 165-182. 

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