Unsteady Hydromagnetic Couette Flow within a Porous Channel

ABSTRACT Unsteady MHD Couette Flow of a viscous incompressible electrically conducting fluid, in the presence of a transverse magnetic field, between two parallel porous plates is studied. The fluid flow within the channel is induced due to the impulsive and uniformly accelerated motion of the lower plate of the channel. The magnetic lines of force are assumed to be fixed relative to the moving plate. Laplace transform technique is applied to obtain the solution for the velocity field. The expression for the non-dimensional shear stress at the lower plate is also derived. The asymptotic solution valid for large time t is obtained to gain some physical insight into the flow pattern. The numerical results for the velocity is depicted graphically for various values of magnetic parameter M2 , suction/injection parameter S and time t whereas numerical values of the shear stress at the lower plate are presented in tabular form for different values of M2 , S and t.