ABSTRACT

The present paper considers the unsteady two-dimensional flow and heat transfer of a viscous and incompressible fluid of uniform ambient temperature past a stretching permeable surface. Initially, two equal and opposing forces are applied along the axis measured along the surface so that the surface is suddenly stretched with velocity keeping the origin fixed. It is also assumed that at time, the surface heat flux is suddenly raised to a constant value. Under these conditions the problem is described by the basic partial differential equations of continuity, momentum, and energy in three independent variables. These equations are transformed into a nondimensional form using a suitable boundary layer transformation. Numerical solutions of these equations (similar, nonsimilar, and series) are determined to study the effects of some values of the governing parameters on the velocity and temperature profiles as well as on the skin friction and dimensionless wall temperature. It is shown that there is a smooth transition from the small time solution (initial unsteady flow) to the large time solution (final time solution). It is also shown that there is excellent agreement between the numerical and analytical solutions.