THEORETICAL INVESTIGATION OF SOLAR RADIATION ON A THIN LIQUID FILM OVER AN UNSTABLE STRETCHING SHEET SURROUNDED BY A POROUS MEDIUM
S. E. Ghasemi, Sina Gouran
Abstract
In present article, the thermohydraulic behavior of a thin liquid film on an unstable stretching surface under the influences of solar radiation and a porous medium is studied. An optimal homotopy asymptotic scheme and differential quadrature method have been utilized for solving the governing equations of temperature and velocity. The precision of the proposed techniques is evaluated by comparison with previous studies. The results will be comprehensively analyzed for varying significant physical variables such as Prandtl number, radiation parameter, Darcy number, and unsteadiness parameter. It can be concluded that both the velocity and temperature profiles are enhanced by raising the unsteadiness parameter. There is an increment of around 46% on the temperature profile and 55% on the velocity profile when the unsteadiness parameter was changed. Moreover, radiation parameter augmentation has a significant effect on enhancing the temperature profile. Further, results reveal that increasing the Prandtl number leads to a severe decrease in the temperature profile.