Natural convection in a porous layer heated and cooled along one vertical side

This paper describes the heat transfer and fluid flow through a confined porous layer heated and cooled along one of the vertical side walls. In the first part of the study, consideration is given to the case when the side-heating effect is positioned above the side-cooling effect. Numerical experiments and scale analysis show that the natural circulation in this first configuration is either one of incomplete vertical penetration, or one of incomplete horizontal penetration. Scale analysis shows that the heat transfer and fluid flow scales differ substantially from one type of penetrative convection to the other, in agreement with the trends revealed by numerical simulations. When the heated portion of the side wall is located below the cooled portion, the flow spreads throughout the porous medium. Scale analysis shows that if the Rayleigh number is sufficiently high, the two mirror-image cells of this flow make contact with the vertical side wall and with each other via slender boundary layer regions. The parametric domain in which the conclusions of this study are valid is outlined on the H/L-Ra H plane, where H/L is the height/length ratio and Ra H is the Darcy-modified Rayleigh number based on porous system height.