HR: 10:20h
AN: H42A-01    [Abstracts]
TI: The Effects of Heterogeneity and Viscosity on Miscible Two-Phase Flow in Porous Media: Pore-Level Modeling
AU: * Ferer, M V
EM: ferer@netl.doe.gov
AF: U. S. Department of Energy National Energy Technology Laboratory, 3610 Collins Ferry Rd P. O. Box 880, Morgantown, WV 26501-0880
AU: Stevenson, K
EM: kstevenson1@hotmail.com
AF: U. S. Department of Energy National Energy Technology Laboratory, 3610 Collins Ferry Rd P. O. Box 880, Morgantown, WV 26501-0880
AU: Bromhal, G S
EM: Bromhal@netl.doe.gov
AF: U. S. Department of Energy National Energy Technology Laboratory, 3610 Collins Ferry Rd P. O. Box 880, Morgantown, WV 26501-0880
AU: Wilder, J
EM: Joseph.Wilder@netl.doe.gov
AF: U. S. Department of Energy National Energy Technology Laboratory, 3610 Collins Ferry Rd P. O. Box 880, Morgantown, WV 26501-0880
AU: Smith, D H
EM: Duane.Smith@netl.doe.gov
AF: U. S. Department of Energy National Energy Technology Laboratory, 3610 Collins Ferry Rd P. O. Box 880, Morgantown, WV 26501-0880
AB: There are long-standing uncertainties regarding the relative significance of the role of porous medium heterogeneities vs. the role of fluid properties in determining the efficiencies of various strategies for fluid injection into porous media. In this presentation, we study both the role of heterogeneities and of viscosity ratio in determining the characteristics of miscible, two-phase flow in two-dimensional (2-d) porous media. Not surprisingly, we find that both are significant in determining the flow characteristics. For a variety a statistical distributions of pore-throat radii, we find that the coefficient of variation (the ratio of the standard deviation of the radii to their mean) is a reliable predictor of the injected fluid saturation as well as the width of the interfacial region. Consistent with earlier results, we find that viscosity ratio causes a crossover from fractal viscous fingering to standard compact flow at a characteristic crossover time which varies inversely with viscosity ratio. These studies show that the power law relating characteristic time to viscosity ratio does not depend upon the distribution of pore throat radii or upon the connectivity (coordination number) of the medium, suggesting that this power law may be entirely independent of the structure of the porous medium. This power law relationship leads to a robust dependence of the flow properties upon a particular ratio of the saturation to a given power of the viscosity ratio. This dependence is reminiscent of the empirical "quarter power mixing rule" in three dimensions (3-d). As such, this work provides a physical understanding of the origin and limitations of this empirical mixing rule.
DE: 1615 Biogeochemical cycles, processes, and modeling (0412, 0414, 0793, 4805, 4912)
DE: 1828 Groundwater hydraulics
DE: 1829 Groundwater hydrology
DE: 1839 Hydrologic scaling
DE: 1847 Modeling
SC: Hydrology [H]
MN: Fall Meeting 2005