| || Oscillating Flow of a Viscous Liquid in a Porous Rectangular Duct
Author : Johri, A.K.;Singh, Man
Source : Defence Science Journal ; Vol:38(1) ; 1988 ; pp 21-27
Subject : 532.542 Fluid Dynamics
Keywords : Fluid dynamics;Viscous incompressible liquid;Darcian effect;Drag
Abstract : The unsteady flow of viscous incompressible liquid in a long porous straight duct of rectangular cross-section, under the influence of periodic pressure gradient using the generalised momentum equation, has been studied. The finite cosine transforms have been employed to solve the problem. Expressions for velocity distribution, volume flow rate (flux) and drag in the duct have been derived. A few particular cases have been deduced. It is found that the classical Darcian effect is felt only in a core very near to the axis of the duct and the non-Darcian phenomenon is felt predominantly, near the boundary of the duct. It is also found that the velocity, volume flow rate (flux) and drag increase with the increase in frequency of oscillations of liquid. Whereas the porosity of the medium reduces both the velocity and flux and increases the drag.