ISSN:
1435-1528
Keywords:
Pseudoplastic flow
;
suspension
;
solid volume fraction
;
ζ-potential
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Abstract The pseudoplastic flow of suspensions, alumina or styrene-acrylamide copolymer particles in water or an aqueous solution of glycerin has been studied by the step-shear-rate method. The relation between the shear rate,D, and the shear stress,τ, in the step-shear-rate measurements, where the state of dispersion was considered to be constant, was expressed asτ = AD 1/2 +CD. The effective solid volume fraction,ø F, andA were dependent on the shear rate and expressed byø F =aD b andA = αD β. Combining the above relations, the steady flow curve was expressed byτ = αD 1/2 + β +η 0 (1 − a D b/0.74)−1.85 D, whereη 0 is the viscosity of the medium. With an increase in solid volume fraction and a decreases in the absolute value of theζ-potential, the flow behavior of the suspensions changed from Newtonian (α = β = b = 0), slightly pseudoplastic (β = b = 0), pseudoplastic (β = 0) to a Bingham-like behavior. The change in viscosity of the medium had an effect on the change in the effective volume fraction.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01331975
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