FLUID-FLOW IN A LAYERED MEDIUM

A layered medium is modeled as a continuous distribution of relatively flat cells within a spatial region. Local now within each cell as wel l as the exchange with the global flow over the region is modeled by a quasilinear parabolic system of partial differential equations, and t he local geometry of the individual cells is included in the model. We introduce new terms to account for the secondary flux corresponding t o either transverse flow across the cells or direct cell-to-cell diffu sion driven by the global density gradient, The resulting initial-boun dary-value problem is shown to be well-posed and to depend continuousl y on the parameter defining the type of interface condition on cell bo undaries.