Steady and unsteady boundary layers due to a stretching vertical sheet in a porous medium using Darcy-Brinkman equation model

The present paper deals with the analysis of steady and unsteady boundary layer flow and heat transfer past a vertical stretching sheet in a viscous fluid-saturated porous medium by using the Darcy-Brinkman equation model. It is assumed that unsteadiness is caused by the impulsive stretching of the sheet and by sudden increase in the surface temperature. The problem is reduced to parabolic partial differential equations, which are solved numerically using the Keller-box method. The small time (initial unsteady flow) as well as the large time (final steady-state flow) solutions are also included in the analysis. It is shown that there is a smooth transition from the small time solution to large time solution, respectively.