HR: 1340h
AN: H33A-1368    [Abstracts]
TI: The Onset of Nonlinear Flow in Three-Dimensional Heterogeneous Flow Domains Based on Energy Dissipation Measures
AU: Meakin, P
EM: meakp@inel.gov
AF: Idaho National Laboratory, P.O. Box 1625, MS 2025, Idaho Falls, ID 83415 United States
AU: * Basagaoglu, H
EM: basagaoh@geo.oregonstate.edu
AF: Department of Geosciences, 202B Wilinson Hall Oregon State University, Corvallis, OR 97331 United States
AU: Succi, S
EM: succi@iac.rm.cnr.it
AF: Instituto Applicazioni Calcolo, CNR-IAC Viale del Poloclinico 137, Rome, 00161 Italy
AU: Welhan, J
EM: welhjohn@isu.edu
AF: Department of Geology, Idaho Geological Survey Idaho State University , Pocatello, ID 83209 United States
AB: The onset of nonlinear flow in three-dimensional random disordered porous flow domains was analyzed using participation numbers based on local kinetic energies, and energy dissipation rates computed via non-equilibrium kinetic tensors. A three-dimensional lattice Boltzmann model was used to simulate gravity-driven single-phase flow over a range of Reynolds numbers that included the crossover from linear to nonlinear flow. The simulations results indicated that the kinetic energy participation number characterized the onset of nonlinear flow in terms of transition to a more dispersed (uniform) distribution of kinetic energy densities as the flow rate increased. However, the energy dissipation participation number characterized the onset of nonlinear flow in terms of a transition to a more locally concentrated distribution of energy dissipation densities at higher flows. The flow regime transition characterized by the energy dissipation participation number occurred over a nearly equal or a narrower range of Reynolds numbers compared to the transition characterized by the kinetic energy participation number. The results also revealed that the boundary conditions (periodic vs. no-slip) parallel to the main flow direction have an insignificant effect on the magnitude of the critical Reynolds number, that characterizes the onset of nonlinear effects, although they did influence the spatial correlations of the pore-scale kinetic energy and the energy dissipation densities in all Cartesian directions. Flow domains with periodic boundaries resulted in less-localized (more dispersed) steady-state flows than domains with no-slip boundaries. These results should be useful for designing future experiment like those of Zeria et al. 2005 (Transport in Porous Media, 60:159-181) that would have significant potential implications in diverse fields.
DE: 1829 Groundwater hydrology
DE: 1847 Modeling
SC: Hydrology [H]
MN: Fall Meeting 2005