UNSTEADY MOTION OF A NON-NEWTONIAN FLUID IN THE ANNULAR SPACE BETWEEN TWO POROUS CONCENTRIC CIRCULAR CYLINDERS

Abstract

The unsteady motion of a non-Newtonian fluid, between two porous concentric circular cylinders, produced by suddenly accelerating the outer cylinder to a constant velocity is investigated. It is assumed that the rate of injection at one pipe is equal to the rate of suction at the other. Explicit expressions for the velocity distribution have been obtained and the effect of cross-viscosity (which is effective only where there is suction and injection) on the time dependent velocity is discussed.