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arXiv · 0711.4804

Flow of power-law fluids in self-affine fracture channels

Yiguang Yan·Joel Koplik
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Abstract

The two-dimensional pressure driven flow of non-Newtonian power-law fluids in self-affine fracture channels at finite Reynolds number is calculated. The channels have constant mean aperture and two values $ζ$=0.5 and 0.8 of the Hurst exponent are considered. The calculation is based on the lattice-Boltzmann method, using a novel method to obtain a power-law variation in viscosity, and the behavior of shear-thinning, Newtonian and shear-thickening liquids is compared. Local aspects of the flow fields, such as maximum velocity and pressure fluctuations, were studied, and the non-Newtonian fluids were compared to the (previously-studied) Newtonian case. The permeability results may be collapsed into a master curve of friction factor vs. Reynolds number using a scaling similar to that employed for porous media flow, and exhibits a transition from a linear regime to a more rapid variation at Re increases.

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Yiguang Yan, Joel Koplik. 2007-11-29. Flow of power-law fluids in self-affine fracture channels. https://doi.org/10.1103/physreve.77.036315

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