THE CHENG-MINKOWYCZ PROBLEM FOR THE TRIPLE-DIFFUSIVE NATURAL CONVECTION BOUNDARY LAYER FLOW PAST A VERTICAL PLATE IN A POROUS MEDIUM

We consider in this paper the extension of the Cheng-Minkowycz boundary layer problem past a vertical plate in a porous medium in the presence of more than one (triple) chemical dissolved in fluid mixtures using the Darcy porous medium model. Both the buoyancy aiding and opposing flows are investigated. Using appropriate similarity variables, the governing partial differential equations are reduced to ordinary (similarity) differential equations, which are then solved numerically using a Fehlberg fourth fifth order Runge-Kutta method. Comparison with the results reported in Bejan and Khair (1985) [Bejan, A. and Khair, K. R., Heat and mass transfer by natural convection in a porous medium, Int. J. Heat Mass Transfer, vol. 28, pp. 909-918, 1985] is made and it is found an excellent agreement. Results for the flow, heat, and concentration characteristics are presented graphically and in tabular form and then discussed.