Flow induced by non-coaxial rotation of a porous disk executing non-torsional oscillations and a second grade fluid rotating at infinity

The purpose of this work is to examine the flow of a fluid bounded by a porous disk. The fluid is assumed to be non-Newtonian (second grade) and incompressible. Such a flow model has great significance not only of its own theoretical interest, but also for application to geophysics and engineering. The governing initial value problem has been solved analytically by using the Laplace transform technique. Explicit expressions for the velocity for steady and unsteady cases have been constructed. The analysis of the obtained results showed that the flow field is appreciably influenced by the material parameter of the second grade fluid, the imposed frequency, rotation and porosity parameters. Several known results of interest are found to follow as particular cases of the solution of the problem considered. (C) 2003 Elsevier Inc. All rights reserved.