This paper reports a numerical study of double-diffusive natural convection
through an annular space delimited by a square cylinder on the outside and a
cylindrical cylinder on the inside covered by a porous layer. The
Darcy-Brinkmann-Forchheimer is used for modeling flow in both fluid and
porous areas. The annular space is partially or completely filled with an
isotropic porous medium. A finite volume method, using the Patankar-Spalding
technique is used for solving the discretization of the dimensionless
equations governing the problem. The effects of simultaneously applied
thermal and solutal buoyancy forces on heat and mass transfer are shown in
the results for a large range of buoyancy ratios N, Rayleigh number, and
thermal conductivity. Streamlines, isotherms, and iso-concentrations are
presented to analyze the flow structure transition from mass species
dominated to thermal dominated flow. Results show that the buoyancy ratio
can change the flow pattern and the increased thermal conductivity ratio can
improve heat and mass transfer. A good agreement was obtained between the
present results and those published were found.
Boundary Element Method for double diffusive natural convection in a horizontal porous layer
