• RUN-UP FLOW OF A RIVILIN-ERICKSEN FLUID THROUGH A POROUS MEDIUM IN A CHANNEL

Abstract

In this paper we analyze the start-up flow of an incompressible Viscoelastic Rivlin-Ericksen fluid. The initial flow is assumed due to the movement of boundaries. At an instant of time t, the boundaries are suddenly brought to rest and the flow is maintained due to a prescribed pressure gradient. The governing equations are solved applying Laplace Transform Technique and the flow characteristics are discussed for different flow variables. The analysis is carried out by considering the pressure gradient in the form c(1 + f(t)) where f(t) is taken in the following forms a) t b) e-t c) te-t d) 0 which corresponds to constant pressure gradient.