## Članak

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Thermal Science
2011, vol. 15, br. 1, str. 67-80
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doi:10.2298/TSCI1101067A

A theoretical and numerical study of thermosolutal convection: stability of a salinity gradient solar pond
(naslov ne postoji na srpskom)
aTheoretical and Applied Fluid Mechanics Laboratory, Faculty of Physics USTHB, Bab-Ezzouar, Algeria
bTheoretical Physics Laboratory, Faculty of Physics USTHB, Bab-Ezzouar, Algeria

### Sažetak

(ne postoji na srpskom)
A theoretical and numerical study of the effect of thermodiffusion on the stability of a gradient layer is presented. It intends to clarify the mechanisms of fluid dynamics and the processes which occur in a salinity gradient solar pond. A mathematical modelling is developed to describe the thermodiffusion contribution on the solar pond where thermal, radiative, and massive fluxes are coupled in the double diffusion. More realistic boundary conditions for temperature and concentration profiles are used. Our results are compared with those obtained experimentally by authors without extracting the heat flux from the storage zone. We have considered the stability analysis of the equilibrium solution. We assumed that the perturbation of quantities such as velocity, temperature, and concentration are infinitesimal. Linearized equations satisfying appropriate prescribed boundary conditions are then obtained and expanded into polynomials form. The Galerkin method along with a symbolic algebra code (Maple) are used to solve these equations. The effect of the separation coefficient y is analyzed in the positive and negative case. We have also numerically compared the critical Rayleigh numbers for the onset of convection with those obtained by the linear stability analysis for Le = 100, µa = 0.8, and f = 0.5.

### Ključne reči

salt gradient; solar pond; solar energy; salinity; thermo diffusion; soret effect; linear stability; numerical simulation

### Reference

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