The Transition Between the Navier–Stokes Equations to the Darcy Equation in a Thin Porous Medium

Abstract

We consider a Newtonian flow in a thin porous medium Ωε of thickness ε which is perforated by periodically distributed solid cylinders of size aε. Generalizing [2], the fluid is described by the 3D incompressible Navier-Stokes system where the external force takes values in the space H^{−1}, and the porous medium considered has one of the most commonly used distribution of cylinders: hexagonal distribution. By means of an adaptation of the unfolding method, three different Darcy’s laws are rigorously derived from this model depending on the magnitude aε with respect to ε.