Finite element analysis of heat transfer by natural convection in porous media in vertical enclosures: Investigations in Darcy and non-Darcy regimes

The finite element scheme for natural convection heat transfer in porous media was applied to vertical enclosures in both low permeability (Darcy) and high permeability (non-Darcy) regimes. The core was observed to be rotating in the streamwise direction, in Darcy regimes, in the case of annular cavities with constant wall temperatures. It was observed that the multi-cellular flow pattern is not as strong as in the case of pure fluids. It was found that the S-shaped profiles are a result of the temperature of the fluid outside the boundary layer being more than that of the fluid at a corresponding point inside the boundary layer.