1 - Modelling fluid flow in saturated porous media and at interfaces

Abstract

This chapter presents modeling fluid flow in saturated porous media and at interfaces. A porous medium is a fixed (or almost fixed) solid matrix with a connected void space through which a fluid can flow. Most porous media are opaque to radiation, and for them the effect of radiation is felt only in thin surface layers. The chapter reviews the refinements that have been made to the equations used to model single-phase fluid flow and heat transfer in a saturated porous medium, to allow for basic things such as inertial effects, boundary friction and viscous dissipation, and additional effects such as those due to rotation or a magnetic field or due to radiative heat transfer. Approaches to modeling flow at a porous-medium/clear-fluid interface are also reviewed in the chapter. It has been demonstrated in the chapter that the modeling of fluid flow in a porous medium involves some subtle matters, but substantial progress has been made in dealing with these matters. There are at least a couple of areas where further investigation is desirable. The first such area is the modeling of high speed fluid flow in a porous medium. The second area where further work is desirable is the problem of modeling the interface between a clear fluid and a mushy zone, where the porosity varies with distance from the interface.