Boundary effects on the onset of nonlinear flow in porous domains

¹ Department of Geosciences, Oregon State University - Corvallis, OR 97331, USA
² Idaho National Laboratory - P.O. Box 1625, MS 2211, Idaho Falls, ID 83415, USA
³ Istituto Applicazioni Calcolo, CNR-IAC - Viale del Policlinico 137, 00161 Roma, Italy
⁴ Department of Geosciences, Idaho State University - Pocatello, ID 83209, USA

Received: 3 October 2005
Accepted: 18 January 2006

Abstract

The effects of flow domain boundaries on the onset of nonlinear flow, and kinetic-energy and energy dissipation densities in three-dimensional heterogeneous porous domains were analyzed. The analyses were based on kinetic-energy and energy dissipation participation numbers, and a 3D lattice Boltzmann model was used to simulate gravity-driven single-phase flow in random porous media. The results revealed that the boundary conditions (periodic vs. no-slip) parallel to the main flow direction have insignificant effects on the magnitude of the critical Reynolds number, that characterizes the onset of nonlinear effects, although it affected the spatial correlations of pore-scale kinetic-energy and 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.