Large Rayleigh number convection in a shallow cavity filled with a porous medium: The intermediate regime.

The steady convective flow generated in a shallow porous cavity by differentially heated end walls is considered in the large Rayleigh number limit for the situation where the aspect ratio L(length/height) of the cavity is comparable to the Raleigh number R based on the cavity height. In this regime the flow departs from the single Hadley-cell structure valid only for very shallow cavities. The behavious in this intermediate regime, R = O(L), forms one part of the complete transition between the flow in very shallow cavity to that in a cavity of finite aspect ratio. Results are obtained for insulated and for conducting horizontal boundaries.