Conjugate mixed convection-conduction heat transfer in porous media

This dessertation studies analytically the conjugate mixed-convection conduction heat transfer in porous media. Solutions for mixed convection flows about vertical plate and cylindrical fins embedded in a porous medium have been obtained by including the effects of interactions between the conduction in the solid boundaries (fins) and the convection in the boundary layer. It has been found that the governing parameters are the Prandtl number Pr, buoyancy force parameter Omega, convection conduction parameter Ncc, and the surface curvature parameter lambda. Extensive results for heat transfer characteristics are presented graphically and in tabular forms for the following ranges of parameters: 0.05 or = Pr or = 7.5, 0.0 or = omega or = 20.0, 0.0 or = Ncc 2.0 and 0.5 or = lambda or = 5.0. Many results were found to have trends similar to those for classical fluids. In particular, the local heat transfer coefficients for mixed convection flows were found not to decrease monotonically as usual, but instead, the coefficients decreased first, attained a minimum value and then increased with increasing streamwise distance. This behavior is attributable to an enhanced buoyancy force resulting from an increase in the wall-to-fluid temperature difference along the streamwise direction.