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Showing 1 to 20 of 44 for “"shear-thickening"”.
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The Ultrasonic Characterization of Shear Thickening Suspensions
… of an inherently inhomogeneous medium capable of shear thickening. An aqueous suspension of cornstarch represents an important exemplar of such physical systems. The physics underlying the behavior of such shear thickening suspensions is incompletely understood. Characterization of these …
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Shear Thickening In Dense Bidisperse Suspensions By Dynamic Simulation
<p>Shear thickening, which corresponds to an increase of viscosity with shear rate, is ubiquitously observed in many concentrated suspensions and, as such, has implications for many industrial materials and geological phenomena. Controlling shear thickening is of significant importance, and many …
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Shear thickening and microstructures of concentrated charge stabilized suspensions
… properties and microstructures as function of shear rates is constructed for the first time. A parameter to measure the degree of suspension order under shear is established. The rapid increase of suspension viscosity as the shear rate increases is examined as function of volume fraction, …
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Energy absorption of reticulated foams filled with shear-thickening silica suspensions
… energy absorbing fluid-composite that utilized a shear thickening fluid is developed. Shear-thickening fluids are a class of field responsive fluids that have the ability to transition from low viscosity to high viscosity under an imposed deformation field. Two different types of silica particles …
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The rheo-optics of shear thickening and structure formation in polymer solutions
… structure formation and the phenomenon of shear-thickening. Transient and steady state measurements of the viscosity, dichroism, birefringence and associated orientation angles were carried out in decalin and bromobenzene in the semi-dilute region using a couette device capable of shear …
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Characterization of shear-thickening fluid-filled foam systems for use in energy absorption devices
… the fluid within these foams is a non-Newtonian shear-thickening fluid composed of 300 nm silica particles suspended in a solvent, ethylene glycol, at high concentrations, 45-55 %. The field of energy absorption using elastomeric foams has been extensively researched in industry. In addition, the …
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Large Scale Simulation of Plate-Like Particle Suspensions
Shear thinning and shear thickening of suspensions of plate-like particles are studied. It is found that shear thinning is caused by both the decrease of the strength of the Brownian motion and the decrease of the hydrodynamic contribution to the viscosity resulting from the increasing particle …
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Flow-Induced Self Assembly in Micellar Fluids with Applications to Nanomanufacturing
… transitions in surfactant solutions under simple shear as well as porous medium flows, and how they are influenced by the presence of added salt First, we study the effect of salt concentration on the shear rheology of ionic surfactant solutions in simple shear flow. It is shown that for a given …
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The Rheology and Microstructure of Dense Bimodal Mixtures of Colloidal Particles With Long-Range, Soft Interactions
… to the monodisperse suspensions for most applied shear stresses. Yield stresses and the general flow curves for all mixtures studied followed the same scaling on the elastic modulus as the monodisperse suspensions. The mixtures display substantial differences in the shear thickening regime. …
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Complex flow of concentrated suspensions
… complex flow behaviour. They can show Newtonian, shear thinning or shear thickening behaviour, depending on the applied stress or shear rate and concentration. The shear thickening behaviour may be discontinuous and this is characterised by a dramatic increase in viscosity above a certain …
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High-rate deformation behavior and applications of fluid filled reticulated foams
… energy absorbing fluid-composite that utilized a shear thickening fluid is developed. Shear-thickening fluids are a class of field responsive fluids that have the ability to transition from a low viscosity state to a high viscosity state under an imposed deformation field. A shear thickening fluid …
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Rheology and Microstructure of Concentrated Suspensions of Plate-Shaped Colloidal Particles
… equal to 8. These suspensions demonstrate shear thickening at $\phi \ge$ 0.50 and also have a shear history dependent elastic modulus, G$\sp\prime.$ In the shear thinning region G$\sp\prime$ decreases with increasing shear rate. In the shear thickening region the modulus increases rapidly. …
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Dilute Non-Newtonian Particle Suspension Rheology And Microstructure
… questions about suspension rheology and shear flow-induced microstructural effects remain. First, a quasi-analytical study is presented that gives the first theory-based predictions on the effects of finite polymer relaxation time on rheological properties. In a constant viscosity, low polymer …
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Swimming in slime
… We compare the swimming speeds of viscoelastic shear thinning, shear thickening and Newtonian fluids for a fixed propagating wave speed. We then compare the swimming speeds of these same fluids for a fixed rate of work per wavelength. In the latter situation, we find that a shear thinning fluid …
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Effect of nonionic surfactant (X-100) on the rheological properties of aqueous polyacrylamide solutions
… are widely used in modern technology as thickening agent, for turbulent reduction and many other uses. They have been extensively used in enhanced oil recovery. In many cases, polyacrylamide comes into contact with surfactants which lead to a change in its rheological properties. In this …
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The Influence of Nonadsorbed Polymer on the Behavior of Weakly Flocculated Suspensions
… of excess PMMA, suspensions exhibited strong shear thinning and low shear relative viscosities ($\eta\sb{\rm rel,0}$) in excess of 10$\sp4$, indicative of their weakly flocculated nature. Correspondingly, total interparticle potential calculations obtained by summing van der Waals and steric …
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The effects of concentration, interaction, size distribution and shape anisotropy on rheology of colloidal mixtures
… dynamic arrest transition, linear elasticity, shear thickening, and yielding for both monomodal and bimodal particle size distributions. Data is reported showing a varied dynamic arrest transition volume fraction, weakened shear thickening behavior and augmented shear elasticity in higher …
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Fracture Morphologies in Particulate Suspensions
… and crack during drying and discontinuously shearthickening suspensions shear-jam and fracture under applied stress. In both systems, the morphology and dynamics of fracture reveal the internal stresses in the material: craquelures in old paintings reveal details of the painting technique …
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Elastic stiffening in PVA-Borax studied with experimental medium amplitude oscillatory shear
… the mechanisms of strain-stiffening and shear-thickening often observed in transient or associative polymer hydrogels; specifically, Poly(vinyl) alcohol (PVA) crosslinked with Sodium tetraborate (Borax), or PVA-Borax. We use medium amplitude oscillatory shear (MAOS) as a tool to measure …
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Variable impedance energy dissipation on the micro-scale : field responsive fluids in novel geometries
… incorporated electrorheological fluid (ERF) and shear-thickening fluid (STF) in novel geometries to absorb compressive and tensile/shear forces. ER and ST fluids change their apparent viscosity in the presence of elevated electric and shear fields, respectively, and the magnitude of this effect …
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