Paper Title:
SPH as an Inverse Numerical Tool for the Prediction of Diffusive Properties in Porous Media
  Abstract

Heat and mass transfer and fluid flow in porous media are usually characterized by, or associated with, the effective thermal conductivity, the effective mass diffusivity and the permeability, respectively. All these macroscopic quantities are conceptually established on a phenomenological “equivalence” basis. They may contain the influence of porous micro-structures upon the corresponding diffusive process; however, the detailed nature inside the porous medium is lumped and neglected. Pore scale numerical modelling has the potential of providing adequate meso-/micro- scale insight into the transport process in porous medium, as well as obtaining macroscopic properties, which can encompass the complex pore-structure details. Modelling heat/mass transfer and fluid flow in complicated porous micro-structures presents a major challenge to numerical methods due to their multiscale and multiphysics nature. A relatively-novel numerical technique - the meshless Lagrangian-based Smoothed Particle Hydrodynamics (SPH) method is thought to be capable of making a significant contribution to this research field. This work deals primarily with the SPH modelling of heat conduction and fluid flow in 2-D isotropic porous media. The porous matrix is formed by randomly including a different component into a base component. Various pore-structures are realized by changing the inclusion shape/size, or the relative arrangement condition between inclusions. Pore-scale heat transfer and fluid flow streams are visualized, and both heat transfer and fluid flow always follow, as expected, the paths of least resistance through the porous structures. In what concerns the effective thermal conductivity, for the porous media with the base component of larger bulk thermal conductivity, the “flexible” EMT model, which can accommodate, to some extent, the influence from the porous micro-structures on the effective thermal conductivity by adjusting the so-called flexible factor ff, gives effective thermal conductivities agreeable to the SPH predictions across the whole composition range if ff is taken to be ~ 4.5; the effective thermal conductivity shows a weak dependence on the inclusion shape/size and the relative arrangement condition between inclusions; however, for porous media with dispersed inclusions, which component has larger bulk thermal conductivity presents a strong effect upon the effective thermal conductivity. The SPH fluid flow simulation results confirm the macroscopic Darcy’s law to be valid only in the creeping flow regime; the dimensionless permeability (normalized by the squared characteristic dimension of the inclusions) is found to have an exponential dependence on the porosity within the intermediate porosity range, and the derived dimensionless permeability /""porosity relation is found to have only a minor dependence on either the relative arrangement condition between inclusions or the inclusion shape/area.

  Info
Periodical
Edited by
Andreas Öchsner and José Grácio
Pages
171-189
DOI
10.4028/www.scientific.net/MSF.553.171
Citation
A. C.M. Sousa, F. Jiang, "SPH as an Inverse Numerical Tool for the Prediction of Diffusive Properties in Porous Media", Materials Science Forum, Vol. 553, pp. 171-189, 2007
Online since
August 2007
Export
Price
$32.00
Share

In order to see related information, you need to Login.

In order to see related information, you need to Login.

Authors: Masakazu Tane, Soong Keun Hyun, Hideo Nakajima
Abstract:We studied the effective electrical conductivity of lotus-type porous nickel with cylindrical elongated pores by applying the extended...
331
Authors: Thomas Fiedler, Andreas Öchsner, Nilindu Muthubandara, Irina V. Belova, Graeme E. Murch
Abstract:In this paper, the Finite Element and lattice Monte Carlo methods are used to calculate the effective thermal conductivity of two models of...
51
Authors: Ana Coh O. Hirschmann, Maria do Carmo de Andrade Nono, Cosme Roberto Moreira Silva
Abstract:Porous ceramics are of great interest due to their numerous potential applications. The objective of the present investigation was to produce...
161
Authors: Yong Yang, Xue Yu Cheng, Zhao Feng Chen, Ren Li Fu, Zhou Chen, Jing Lian Qiu, Dan Su
Chapter 1: Material Engineering and Technology
Abstract:The influence of density on the thermal conductivity of fiberglass felt is studied by experiment.Experimental data obtained using the...
33