Modelling of non-Newtonian purely viscous flow through isotropic high porosity synthetic foams

A unified modelling theory for the prediction of the pressure drop of non-Newtonian purely viscous flow through isotropic high porosity synthetic foams is proposed. The model is derived by volumetrically averaging the equations of motion over an arbitrary two-phase system of stationary solids and a traversing fluid. Closure is obtained by using a formerly introduced rectangular representation of the pore space morphology. The shear rate dependency of the viscosity is incorporated through the sheer stress in terms of the power-law model. The proposed model, which is based purely on physical principles with no artificial adjusting parameters, is compared to other predictive models in terms of friction factor as a function of the Reynolds number. Predicted pressure drop results are also compared to published experimental results to verify the validity of the model. (C) 1999 Elsevier Science Ltd. All rights reserved.