Convection induced by inclined gradients in a shallow porous medium layer

A review is made of recent convection studies in a shallow layer of a satur ated porous medium, induced by applied thermal and/or solutal gradients. Th is problem is likely to be paradigmatic for convection induced by such grad ients in more general geometries. A horizontal gradient induces a "Hadley c irculation," which can be superimposed on any existing forced convection fl ow The stability of the combined basic flow depends on the horizontal and v ertical components of the inclined gradients. Above a certain vertical grad ient value an additional cellular flow is superimposed on the basic flow Th e nature of the additional cellular flow (e.g., stationary or oscillatory h orizontal rolls whose axes are perpendicular to the vertical gradient and a ligned with or perpendicular to the horizontal gradient), depends on the pa rameters involved.