HR: 08:00h
AN: H21H-01    [Abstracts]
TI: Pore-Scale Study of Drainage Displacement Under Combined Capillary and Gravity Effects in Index-Matched Porous Media
AU: * Ovdat, H
EM: hanita.ovdat@weizmann.ac.il
AF: Weizmann Institute of Science, Department of Environmental Sciences and Energy Research, Rehovot, 76100 Israel
AU: Berkowitz, B
EM: brian.berkowitz@weizmann.ac.il
AF: Weizmann Institute of Science, Department of Environmental Sciences and Energy Research, Rehovot, 76100 Israel
AB: Fluid displacement patterns were observed in two- and three-dimensional (2D, 3D), gravity-driven drainage experiments. A non-intrusive, laser-induced fluorescence technique, using refractive index matching between solid and fluid phases and subsequent imaging processing, enabled measurement of the flow patterns in porous media. The methodology allows visualization of 3D pore-scale flow dynamics of two immiscible fluid phases in porous media at a low capillary number (Ca = 10^-4). Qualitative analyses indicate considerable diversity in the 2D and 3D displacement patterns of the invading fluid within and among the experimental systems. Quantitative analyses of these patterns, however, provide unique functional forms that characterize the invasion behavior of the nonwetting fluids, with clear differences in behavior between 2D and 3D systems. In particular, scaling relations are defined which describe the maximum advance, volumetric fraction, total surface area (or, equivalently, the ratio of total surface area to volume), and specific surface area of the invading fluid. These findings are in excellent agreement with predictions from dynamic invasion percolation growth models, which were developed originally without consideration of buoyancy effects.
DE: 1829 Groundwater hydrology
DE: 1832 Groundwater transport
SC: Hydrology [H]
MN: Fall Meeting 2005