A solution of the laminar flow for a gradual transition between porous and fluid domains

Abstract

Despite its importance, the problem of transfer phenomena at the interface between porous domains and homogeneous free flows found no complete general solution. In this study we contribute to the solution of the problem by studying the effect of a gradual geometrical change at the interface. Such a geometrical change is common to all cases, depending on the scale of observation. We apply the one-domain approach, assume that the porosity profile is given, use a permeability profile as a function of porosity, and generate excellent predictions by applying, when necessary, the concept of the apparent interface location. The apparent interface location serves as an empirical measure providing the degree of freedom needed to match the solution with measured quantities such as the flow rate or a known velocity. Copyright 2010 by the American Geophysical Union.