A DETERMINATION OF THE EFFECTIVE VISCOSITY FOR THE BRINKMAN-FORCHHEIMER FLOW MODEL

The effective viscosity mu e for the Brinkman-Forchheimer flow (BFF) m odel has been determined experimentally for steady flow through a wall -bounded porous medium. Nuclear magnetic resonance (NMR) techniques we re used to measure non-invasively the ensemble-average velocity profil e of water flowing through a tube filled with an open-cell rigid foam of high porosity (phi = 0.972). By comparing these data with the BFF m odel, for which all remaining parameters were measured independently, it was determined that mu(e) = (7.5(-2.4)(+3.4))mu(f), where mu(f) was the viscosity of the fluid. The Reynolds number, based upon the squar e root of the permeability, was 17.