Analytical and numerical solutions of a coupled non-linear system arising in a three-dimensional rotating flow

Hydromagnetic flow between two horizontal plates in a rotating system, where the lower is a stretching sheet and the upper is a porous solid plate (in the presence of a magnetic field), is analyzed. The equations of conservation of mass and momentum are reduced to a system of coupled non-linear ordinary differential equations. These basic non-linear differential equations, for the velocity field (f',f,g), are solved numerically by using a fourth-order Runge-Kutta integration scheme. The numerical results thus obtained are validated by the analytical results (for small R) obtained by the perturbation technique and presented through graphs. Also, the effects of the non-dimensional parameters R, lambda, M-2 and K-2 on the velocity field are discussed, and it is shown that for large K-2, the coriolis force and the magnetic field that act against the pressure gradient cause reverse flow. (C) 2003 Elsevier Science Ltd. All rights reserved.