Gravity-Driven Instability in a Liquid Film Overlying an Inhomogeneous Porous Layer

A new model consisting of a liquid film overlying a saturated and inhomogeneous porous layer is investigated. We concentrate on effects of inhomogeneity on transition of instability modes. Influences of the averaged porosity and the gradient of porosity distribution on the instability behaviors of a liquid-porous layer system are emphasized. The average permeability of the porous layer is a key factor to determine the penetration of convection in the system.