A small unsteady perturbation on the steady hydromagnetic boundary-layer flow past a semi-infinite plate

Abstract

This paper is concerned with the unsteady hydromagnetic boundary-layer flow past a semi-infinite flat plate when the oncoming free stream is perturbed by an arbitrary function of time and the applied magnetic field is parallel to the plate far away from it. Following Lighthill, the two-dimensional boundary-layer equations are separated into those representing steady and unsteady parts of the flow and they have been solved in sequence. For the unsteady part of the motion two types of solutions are obtained, one for large times and the other for small times. Also the quasi-steady solution is obtained in terms of the steady solution. The skin friction and the tangential magnetic field at the plate are calculated.

On Magnetohydrodynamic Unsteady Flows with Induced Field Over A Stretching Surface

“…The unsteady laminar incompressible flow of a viscous electrically conducting fluid with constant properties past a semi-infinite flat plate with aligned magnetic field, without heat transfer, has been studied by Greenspan and Carrier [7], Glauert [8] Gribben [9] and Na [10]. The unsteady boundary layer flow over a stationary semi-infinite plat plate in the presence of magnetic field has been studied by Das [11], Ingham [12], and Goyal and Bansal [13] when the free stream velocity is changed impulsively.…”