Near-wall particle depletion in a flowing colloidal suspension

  title={Near-wall particle depletion in a flowing colloidal suspension},
  author={Paul J. A. Hartman Kok and Sergei G. Kazarian and Christopher J. Lawrence and Brian J. Briscoe},
  journal={Journal of Rheology},
In this paper a method based on attenuated total reflection–Fourier-transform infrared spectroscopy is described to measure the concentration of colloidal particles dispersed in a liquid near a solid boundary in pressure driven flows. The method has been used to obtain measurements of wall depletion in an aqueous suspension of ethylcellulose particles. The method is capable of measuring the particle concentration in a thin layer near the boundary, whose thickness is between 0.3 and 1.4 μm. A… 
Effects of particle size on near-wall depletion in mono-dispersed colloidal suspensions.
It was found that wall depletion was not significant for Peclet numbers smaller than unity, and estimates of the wall slip layer thickness obtained from rheological experiments were consistent with the results obtained by ATR-IR spectroscopy.
Wall slip of concentrated suspension melts in capillary flows
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A review on wall slip in high solid dispersions
High solid dispersions are soft materials made of colloidal or non-colloidal particles dispersed at high volume fractions in a liquid matrix. They include hard sphere glasses, colloidal pastes,
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A mathematical model developed earlier for the time-dependent circular tube flow of compressible polymer melts subject to pressure-dependent wall slip [Tang and Kalyon, J. Rheol 52, 507–525 (2008)]
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An experimental adaptation of the well-known laser-Doppler anemometry technique is developed for measuring the velocity and concentration profiles in concentrated suspension flows. To circumvent the
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The intensity of light scattered from a suspension of colloidal latex particles near an interface and subjected to flow was measured as a function of the penetration depth of an evanescent wave and
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Abstract Slip occurs in the flow of two-phase systems because of the displacement of the disperse phase away from solid boundaries. This arises from steric, hydrodynamic, viscoelastic and chemical
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The shear-induced particle self-diffusivity in a concentrated suspension (20%–50% solids volume fraction) of non-colloidal spheres (90 [mu]m average diameter) was measured using a new correlation
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This study focuses on the demixing of neutrally buoyant suspensions of spheres during slow, pressure driven flows in circular conduits. Distributions of the solid fraction of particles, φ, and the
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Dynamic simulations of the pressure-driven flow in a channel of a non-Brownian suspension at zero Reynolds number were conducted using Stokesian Dynamics. The simulations are for a monolayer of
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A non-invasive experimental technique which enables optical penetration into the bulk of a flowing liquid-solid concentrated suspension was employed to study such flows. Matching of refractive
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The shear viscosity material function of a highly filled suspension consisting of a Newtonian poly(butadiene acrylonitrile acrylic acid terpolymer) matrix, PBAN, mixed with an ammonium sulfate filler
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Often for slurries, gels, emulsions, and foams inhomogeneous fluid properties at solid boundaries create “apparent wall slip.” The reduced fluid viscosity at the boundary creates a thin layer of
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The application of nuclear magnetic resonance (NMR) flow imaging to the study of Poiseuille flows of single‐phase fluids and solid/liquid suspensions is demonstrated and investigated. Two fluids were