Thermal instability of two horizontal porous layers with a conductive partition

Abstract

The stability of two horizontal porous medium layers with a conductive partition is analysed by a linear stability theory. The upper cooled surface and the lower heated surface are taken to be isothermal and both are impermeable. The resulting eigenvalue problem is solved by a Galerkin method. The parameters affecting the stability limit are the ratio of two porous layer thicknesses, the ratio of partition thickness to total porous layer thickness, and the ratio of porous medium conductivity to partition thermal conductivity. Results show the system is most stable when the partition is located in the middle. In addition, as the partition thickness increases or the partition conductivity decreases, the system becomes more stable.