Natural convection in a concentric annulus with a porous sleeve

Analytical solutions obtained through perturbation method and Fourier transform are presented for natural convection in concentric cylinders with a porous sleeve. The porous sleeve is press-fitted to the inner surface of the outer cylinder. Both the inner and outer cylinders are kept at constant temperatures with the inner surface at a slightly higher temperature than that of the outer. The main objective of the present study is to investigate the buoyancy-induced flow as affected by the presence of the porous layer. A parametric study has been performed to investigate the effects of Rayleigh number, Darcy number, porous sleeve thickness, and relative thermal conductivity on the heat transfer results.