Effect of Viscous Dissipation on the Darcy Forced-Convection Flow Past a Plane Surface
E. Magyari, Ioan Victor Pop, B. Keller · Journal of Porous Media · 2003
The uniform forced-convection flow in a fluid-saturated porous medium adjacent to a plane surface with prescribed temperature distribution Tw = Tw(x) is considered. The effect of viscous dissipation is included in the energy balance equation as a quadratic term of the Darcy velocity (see Bejan, 1984, 1995). It is shown that the usual asymptotic condition T (x, y ® Ґ) = const, єTҐ (as it was applied in some recent publications dealing with mixed-convection problems) contradicts this balance equation. In the present paper, -the appropriate asymptotic condition (a linear function of x) is specified and it is shown that this steady forced-convection problem can formally be reduced to a standard transient heat conduction problem in a homogeneous semi-infinite solid. By exploiting this analogy, several examples solvable in exact analytic form are presented.