SINOPSIS

The microstructure of porous media is basically characterized by the geometry of voids and the solid phase. The arrangement of discrete regions, if either the solid phase or voids can be considered as a discrete phase, will have great effects on conduction and convection transport of heat through the porous medium. The relation between the geometry and transport properties of a porous medium is scientifically and technologically important. In the present study, we have presented a numerical simulation in a two-dimensional geometry to ascertain the influence of microstructural characteristics on the transport properties of porous media composed of discrete phases. Heat transfer is simulated in a rectangular porous domain subjected to symmetry boundary conditions on two opposite lateral sides and two inlet and outlet boundaries on the other sides. The domain is composed of a number of discrete regions (objects) with elliptic and circular cross-sections that are arranged in either an ordered or a disordered fashion with given boundary conditions on the surface of the objects. Results lead us to some interesting features of conductive and convective heat transfer in porous media that are associated with the above-mentioned microstructural properties. The surface temperature of the discrete phase and the fluid temperature depend strongly on the Re and Nu numbers in convective flows. On the other hand, conductive heat transfer characteristics through the medium are significantly dependent on the ratio of the conductivities of both phases.