Magnetohydrodynamic flow between two parallel porous walls with time-varying suction

Unsteady motion of an electrically conducting liquid between two parallel porous plates has been considered in this paper when there is time-varying suction at the plates. There is also a transverse magnetic field at the plates. The induced magnetic field has been neglected. The lower plate is at rest and the upper plate moves periodically with a constant mean. The suction velocity at the plate varies periodically with a constant non-zero mean. The flow phenomenon has been characterized by the parameters S (magnetic parameter), ω (frequency parameter) and A (variable suction parameter) and the role of these parameters on the flow characteristics has been studied. (author)