A numerical study of natural convection in a vertical cylindrical enclosure filled with a fluid-saturated porous medium using a three-dimensional model

This work considers the behavior of a vertical cylinder filled with fluid-saturated porous media. In particular, the focus is on the process of natural convection within the cylinder when the vertical surface is exposed to a constant heat flux, heating the interior of the cylinder. While many previous numerical studies of similar geometries were completed in two-dimensional space at steady-state, the present work uses a three-dimensional and transient model. A number of simulations are run involving a range of variables, helping to determine the effects of a few controlling parameters on the cylinder's overall thermal behavior. The control parameters analyzed are the Darcy number, the Rayleigh number, the modified Prandtl number, and the inertial form coefficient. The results indicate for symmetric heating that the Darcy number seems to have a predominant effect on the natural convection process inside the cylinder for the data range considered, with the inertial form coefficient and the modified Prandtl number having little effect. For asymmetric heating, the resulting Nusselt number was higher while the temperature results were lower. Hence, if heating the porous medium is the objective a symmetric heating of the cylinder is preferable.