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Pore-level computational modelling and simulation have recently become the focus of considerable attention in the field of transport in porous media. This study presents pore-structure characterisation and computational fluid dynamics (CFD) modelling and simulation of fluid flow distribution across ‘real’ and ‘structure-adapted’ porous metallic structures derived from tomography datasets at the microscale level. The resulting CFD predicted pressure drop data as a function of superficial fluid velocity ranging between 0 and 6.0 m.s−1 were used to account for the viscous (permeability, k 0) and inertial (Form drag coefficient, C) terms of the porous samples. CFD modelling confidence was established by validating with experimental measurements for foam samples available in the literature. Exprerimental values of k 0 were found to be consistent with values available in the literature, while observable deviations of experimental measurements of C from predicted values (in some cases) strongly support the reliability of the inertial terms in superficial fluid flow velocity, nature of fluid, and level of extended tortuous pathway in porous metallic structures. The adaptation of the ‘real’ structures through erosion and dilation of their skeletal phases enabled the creation of ‘semi-virtual’ structures; thereby providing an in-depth understanding of the manifestation of flowing fluid from Darcy to inertial and a graphical relationship linking pore-structure related parameters and fluid flow properties of the porous media was substantiated.

Abstract:The unsteady, laminar hydro magnetic flow of an incompressible, viscous and electrically conducting Newtonian fluid over a contracting sheet embedded in a porous medium has been investigated. The flow takes place between two parallel flat sheets that are made of an electrically non-conducting material. The fluid is subjected to transverse magnetic field that cuts perpendicularly across the flow in the positive direction of the z-axis. The contracting sheet has a permeable surface while the surface of other sheet is impermeable, each sheet has an isothermal surface and both sheets are kept at different temperature of T W andT ∞ such that the temperature differences within the flow are sufficiently small. The effect of varying various parameters on the velocity and temperature profiles has been discussed. The coupled non-linear partial differential equations governing the flow have been solved numerically using the finite difference method because of its accuracy, stability and convergence. The results that are obtained are then presented graphically and observations have been discussed. Changes in various parameters have been observed to alter the velocity profiles and temperature profiles.

The flow of an electrically conducting incompressible fluid due to buoyancy effects of thermal and mass diffusion past a finite vertical porous plate with constant suction was investigated in the presence of uniform transverse magnetic field. The problem has been solved for velocity, temperature and concentration profiles. The equations governing the flow are solved numerically using finite difference method for various values of Grashof parameter ranging from 0 to -1. The results obtained are then presented using tables and graphs. It was noted that a decrease in Grashof parameter leads to an increase in primary, secondary, temperature and concentration profile.