OSCILLATORY THREE DIMENSIONAL FLOW AND HEAT AND MASS TRANSFER THROUGH A POROUS MEDIUM IN PRESENCE OF PERIODIC SUCTION

The behaviour of unsteady free convective combined heat and mass transfer flow of a viscousincompressible fluid over a infinite vertical porous plate embedded with porous medium of timedependent permeability have been investigated. It is consider that, the transverse permeability ofthe porous medium fluctuates with time and the porous plate is subjected to a transverse sinusoidal suction velocity. The unsteadiness is due to the time-dependent porous medium as well as suction velocity. The governing boundary layer equations with the boundary conditions are first converted into dimensionless form by non-similar transformations, and then resulting system of coupled non-linear partial differential equations are solved by series expansion method. The analytical solutions of the transient, and transverse velocity components, temperature profile, concentration profile, and the skin-friction are reported in the present study. It is found that, higher Prandtl number (Pr = 11.4) causes thinner boundary layer and higher Schmidt number (Sc = 2.57) causes thinner concentration boundary layer. On the other hand, when thermal and mass Grashof numbers were increased, the thermal and concentration buoyancy effects were enhanced and thus, the fluid velocity increased.