Transport in Porous Media, Vol.45, No.2, 283-302, 2001
Fluid flows through two-dimensional channels of composite materials
The present analysis relates to the study of the full two-dimensional Brinkman equation representing the fluid flow through porous medium. The steady, incompressible fluid flow, with a negligible gravitational force, is constrained to flow in an infinitely long channel in which the height assumes a series of piecewise constant values. The control volume method is used to solve the Brinkman equation which involves the parameter, alpha = Gamma /Da, where Da is the Darcy number and Gamma is the ratio of the fluid viscosity mu (f) to the effective viscosity <()over tilde>. An analytical study in the fully developed section of the composite channel is presented when the channel is of constant height and composed of several layers of porous media, each of uniform porosity. In the fully developed flow regime the analytical and numerical solutions are graphically indistinguishable. A geometrical configuration involving several discontinuities of channel height, and where the entry and exit sections are layered, is considered and the effect of different permeabilities is demonstrated. Further, numerical investigations are performed to evaluate the behaviour of fluid flow through regions which mathematically model some geological structures of various sizes, positions and permeability, for example a fault or a fracture, where the outlet channel is offset at different levels. The effect on the overall pressure gradient is also considered.
Keywords:fluid flow;Brinkman equation;interface region;analytical solutions;CFD;control volume method;numerical solutions