Observations of 3-D transverse dispersion and dilution in natural consolidated rock by X-ray tomography
File(s)
Accepted version
Author(s)
Boon, M
Bijeljic, B
Niu, B
Krevor, S
Type
Journal Article
Abstract
Recent studies have demonstrated the importance of transverse dispersion for dilution and mixing of solutes but most observations have remained limited to two-dimensional sand-box models. We present a new core-flood test to characterize solute transport in 3-D natural-rock media. A device consisting of three annular regions was used for fluid injection into a cylindrical rock core. Pure water was injected into the center and outer region and a NaI solution into the middle region. Steady state transverse dispersion of NaI was visualized with an X-ray medical CT-scanner for a range of Peclét numbers. Three methods were used to calculate Dt: (1) fitting an analytical solution, (2) analyzing the second-central moment, and (3) analyzing the dilution index and reactor ratio. Transverse dispersion decreased with distance due to flow focusing. Furthermore, Dt in the power-law regime showed sub-linear behavior. Overall, the reactor ratios were high confirming the homogeneity of Berea sandstone.
Date Issued
2016-08-01
Date Acceptance
2016-07-30
Citation
Advances in Water Resources, 2016, 96, pp.266-281
ISSN
0309-1708
Publisher
Elsevier
Start Page
266
End Page
281
Journal / Book Title
Advances in Water Resources
Volume
96
Copyright Statement
© 2016 Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/
Sponsor
Qatar Shell Research and Technology Center QSTP LLC
Grant Number
490000724
Subjects
Environmental Engineering
0905 Civil Engineering
0907 Environmental Engineering
Publication Status
Published