THE INFLUENCE OF RADIATION ABSORPTION ON SOLAR POND STABILITY

This paper presents a study of the gravitational stability of a salty layer of a fluid subject to an adverse temperature gradient as a resul t of heat absorption. This is intended to model solar ponds where an a rtificial gradient of salt concentration in water is used to prevent c onvective motions induced by the absorption of solar radiation. The st ability of the Boussinesq approximation of the Navier-Stokes equations is analysed for perturbations of a certain kind imposed on the statio nary solution. The marginal slates for the onset of convection are obt ained using a Galerkin method based on a weak formulation of the gover ning equations. The analysis considers solar energy absorption in the layer and assumes prescribed heat flux values as boundary conditions f or the temperature equation. Results are compared with those obtained earlier by different authors for a layer of fluid, heated from below, with linear profiles of both salt concentration and temperature. Copyr ight (C) 1996 Elsevier Science Ltd.