Table of Contents Author Guidelines Submit a Manuscript
Geofluids
Volume 2017 (2017), Article ID 4517259, 24 pages
https://doi.org/10.1155/2017/4517259
Research Article

Computing and Comparing Effective Properties for Flow and Transport in Computer-Generated Porous Media

King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia

Correspondence should be addressed to Shuyu Sun; as.ude.tsuak@nus.uyuhs

Received 18 October 2016; Accepted 7 December 2016; Published 13 February 2017

Academic Editor: Micol Todesco

Copyright © 2017 Rebecca Allen and Shuyu Sun. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

We compute effective properties (i.e., permeability, hydraulic tortuosity, and diffusive tortuosity) of three different digital porous media samples, including in-line array of uniform shapes, staggered-array of squares, and randomly distributed squares. The permeability and hydraulic tortuosity are computed by solving a set of rescaled Stokes equations obtained by homogenization, and the diffusive tortuosity is computed by solving a homogenization problem given for the effective diffusion coefficient that is inversely related to diffusive tortuosity. We find that hydraulic and diffusive tortuosity can be quantitatively different by up to a factor of ten in the same pore geometry, which indicates that these tortuosity terms cannot be used interchangeably. We also find that when a pore geometry is characterized by an anisotropic permeability, the diffusive tortuosity (and correspondingly the effective diffusion coefficient) can also be anisotropic. This finding has important implications for reservoir-scale modeling of flow and transport, as it is more realistic to account for the anisotropy of both the permeability and the effective diffusion coefficient.