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.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1-24 |
| Number of pages | 24 |
| Journal | Geofluids |
| Volume | 2017 |
| DOIs | |
| State | Published - Feb 13 2017 |
Bibliographical note
KAUST Repository Item: Exported on 2020-10-01Acknowledgements: The authors gratefully acknowledge that the research reported in this publication was supported by funding from King Abdullah University of Science and Technology (KAUST). The authors gratefully acknowledge and thank Dr. Francisco J. Valdés-Parada for providing the diffusive tortuosity results for in-line array of circle and square geometries, which were used for comparison in Figure 6 with permission.