Rheology fluids

Borate-crosslinked fracturing fluids have been successfully used in fracturing operations. These fluids provide excellent rheologic, fluid loss, and fracture conductivity properties over fluid temperatures up to 105° C. The mechanism of borate crosslinking is an equilibrium process that can produce very high fluid viscosities under conditions of low shear [336]. [Pg.255]

Tao, R. (Ed.), Electro-Rheological Fluids and Magneto-Rheological Suspensions, World Scientific Publishing Co. Hackensack, NJ, 2000. [Pg.429]

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... [Pg.282]

Nakano M, KoyamaK (eds) (1997) Electro-rheological fluids, magneto-rheological suspensions and their applications. World Scientific, Hackensack, NJ... [Pg.188]

Water-Soluble Polymers. A number of water-soluble polymers are used extensively to control the rheological, fluid loss and shale stabilising properties of water-based drilling fluids. List I lists commonly used polymers and Figure 4 shows the structure of several polymer molecules. Several recent reviews of water-soluble polymers in drilling fluids are available (22-25) McCormick et al. (26) have given a recent useful introduction to water-soluble polymers. [Pg.468]

The areas of science and technology that are spanned by drilling fluids are considerable rheology, fluid mechanics, colloid science, polymer... [Pg.550]

A great deal of the mathematical background for understanding rheology is related to vectors and tensors. A comprehensive discussion of these subjects is out of the scope of this work. However, in what follows in this section, a brief summary of some of the mathematical relationships and quantities of common use in polymer rheology is presented. The reader interested in more details may refer to rheology, fluid, and solid mechanics textbooks [8-13]. [Pg.439]

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. [Pg.43]

Rheological fluids are generally a dispersion composed of a base fluid (usually a type of oil) and particles. These particles can be either polymer in electrorheological fluids (ERF) or iron based in magnetorheological fluids (MRF). If a field is applied, the so-called particle chains are built and the fluid changes its viscosity to the point of becoming a viscoelastic solid (see Fig. 11). [Pg.16]

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. [Pg.753]

The given presentation of the mechanism of the interaction of polymer molecules with turbulent flow admits a peculiar theoretical examination. The presence of polymer addition besides the increase of longitudinal viscosity is resulted in the appearance of such rheological solution properties as elastic plasticity, pseudo-plasticity, anisotropy. In [3] the influence of different rheological fluid characteristics on the wall turbulence is theoretically analyzed within the limits of monoharmonic approximation, which affords to take into account turbulent blows-out. Different variants of rheological behaviour were considered. For all that we succeded to show, that the decrease of turbulent friction arose only in mediums, possessing... [Pg.103]

They have an impression of its high-voltage resistance through their examination as a base oil of the electric rheological fluid (ERF). [Pg.277]

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. [Pg.163]

The systems of dipolar particles considered in this review are simple models for fluids or solids whose molecules bear a permanent dipole moment. They can also serve as credible models for suspensions like ferrofluids [1] or elec-tro(magneto)rheological fluids [2,3]. For spherically symmetric dipolar particles the interaction between a pair of particles separated by a distance nj and bearing dipole moments Hi and fij is given by... [Pg.164]

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... [Pg.224]

Sedimentation (MICROSCOPIC PROCESS) motion of particles in viscous media due to gravitation or centrifugal fields (also settling), the term refers frequently to the state in which the field forces are counterbalanced by the drag force this state is almost instantaneously achieved in the case of colloidal suspensions the sedimentation of an individual particle depends on its size, the density contrast, the rheological fluid properties, the field strength, and the viscous interactions with other particles. [Pg.295]

The dissipative (or viscous or deviatoric) part of the stress tensor (II ) is a function of the rheological fluid properties and depends on the local shear rates. For Newtonian fluids, which are isotropic, purely viscous, and without rheological memory , this dependency is linear (Cauchy-Poisson-law) ... [Pg.302]

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. [Pg.34]

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... [Pg.287]

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... [Pg.288]

Carlson, J.D. Catanzarite, D.M. and St. Clair, K.A. Commercial Magneto-Rheological Fluid Devices. Proc. 5th Int. Conf on ER Fluids, MR Fluids and Assoc. Tech., Sheffield (July 1995), W.A. Bullough, ed.. World Scientific, Singapore (1996), pp. 20-28... [Pg.288]

Duclos, T.G. Design of Devices Using Electro-rheological Fluids. Soc. Auto. Engineers, SAE Paper 881134 (1988)... [Pg.289]

Sodeyama, H. Sunakoda, K. Suzuki, K. Carlson, J.D. and Spencer, B.F. Development of Large Capacity Semi-Active Vibration control Device Using Magneto-Rheological Fluid. Proc. ASME Pressure Vessel and Piping Conf.,... [Pg.290]

Hesselbach, J. Abel-Keilhack, C. Active hydrostatic bearing with magneto-rheological fluid. J. Appl. Phys., Vol. 93, No. 10 (2003), pp. 8441-8443... [Pg.465]

DAMPER WITH ELECTPO-RHEOLOOICAL AND mACNETO-RHEOLOGICAL FLUIDS... [Pg.278]

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