Begell House
Journal of Porous Media
Journal of Porous Media
1091-028X
9
1
2006
Forced Pulsating Flow and Heat Transfer in a Tube Partially Filled with a Porous Medium
The aim of this paper is a numerical simulation of a forced pulsating laminar flow into a cylinder partially filled with a porous medium and the associated transport process. The porous substrate is attached to the inner side of the cylinder wall, which is exposed to a constant heat flux. The flow within the porous domain is modeled by the Brinkman−Lapwood−Forchheimer-extended Darcy model. The mathematical model for energy transport is based on the local thermal equilibrium assumption.
The control volume-based finite element method (CVFEM) is used for solving the differential equations system with an unequal order velocity-pressure interpolation. The effects of the Darcy numbers, the porous layer thickness, the pulsation amplitude and frequency, the thermal conductivity ratio, and the heat capacity ratio are investigated.
Dhahri
Hacen
National school of Engineers Laboratory of Thermal and Energy Systems Studies Monastir University, Ibn Eljazzar Street, 5019 Monastir, Tunisia
A.
Boughamoura
Laboratoire d'Etudes des Systèmes Thermiques et Energétiques, Ecole Nationale d'Ingénieurs de Monastir, Rue Ibn Eljazzar, 5019 Monastir, Tunisie
Sassi Ben
Nasrallah
Laboratoire d'Études des Systèmes Thermiques et Énergétiques, Ecole Nationale d'Ingénieurs
de Monastir, Monastir 5019 Tunisie
1-14
Constitutive Modeling for Hot Isostatic Pressing of Metal Powders
A phenomenological constitutive modeling is proposed for thermomechanical behavior of materials during hot isostatic pressing (HIP) of metal powders. Based on the same approach for the can and powder materials, this modeling deals with an elasto-plastic-viscoplastic concept for material deformation. The model's advantage is its applicability to a larger domain of stress and temperature in comparison to the plastic or ideal viscoplastic models. For elasto-plastic-viscoplastic modeling, the necessary formalisms to calculate the plastic and viscoplastic contributions of inelastic deformation are firstly introduced. A major part of the paper concerns formulating the model, especially the plastic contribution. Identification of the model parameters by some experiments presented in the literature and the model validation by some new experiments will be explained after theoretical assessment of the model.
Gholamreza
Aryanpour
Department of Materials Engineering, Isfahan University of Technology, 84156 Isfahan, Iran
15-34
Modeling of Gas Flow through Isotropic Metallic Foams
Because of their high porosity and especially their very high surface area, metal foams find application in various engineering processes such as gas distributors in fuel cells. Thus, there is a need for the prediction of the pressure drops for given fluid flow rates. In this paper, we present an improvement of the hydraulic model proposed by Du Plessis et al. (1994) adapted to isotropic metallic foam structures in which stagnant zones could exist. Experimental results for airflow through two different metallic foam structures (stainless steel and aluminum foams) are analyzed by application of the theoretical model and the results interpreted. The foams differ because of larger localized solid chunks at the strand interconnections and covered faces of some pores in the stainless steel foams than in aluminum foams. The results show that the submodel, in which there are no stagnant zones, allows good predictions of pressure drop without any fitting parameters for the aluminum foam, knowing the mean strand diameter and the porosity of the foam. In the case of stainless steel foam, results suggest that a combined model of the doubly staggered model and the granular model (Du Plessis and Masliyah, 1991) must be developed.
Sonia
Crosnier
CEA, 17 rue des Martyrs, 38054 Grenoble, France
Jean Prieur Du
Plessis
Department of Applied Mathematics, University of Stellenbosch, Private Bag X1, 7602 Matieland, South Africa
Roland
Riva
CEA, 17 rue des Martyrs, 38054 Grenoble, France
Jack
Legrand
LUNAM Université, GEPEA, Universite de Nantes, Ecole des Mines de Nantes, ENITIAA-CRTT-IUT, BP 406, 44602 Saint-Nazaire Cedex, France
35-54
A Mathematical Model of Peristalsis in Tubes through a Porous Medium
The problem of peristaltic motion in a tube through a porous medium has been investigated. The mathematical model considers a Jeffrey incompressible fluid. The wavelength of the traveling wave is assumed to be large. Analytical expressions for the stream function, axial velocity, and pressure gradient have been obtained. Numerical computations are performed for pressure drop and frictional force per wavelength. The effect of various parameters on the flow is discussed with the help of graphs.
Masood
Khan
Department of Mathematics, Quaid-i-Azam University, Islamabad 44000, Pakistan
Saleem
Ashgar
Department of Mathematical Sciences, COMSATS Institute of Information Technology, Islamabad, Pakistan
Abdul Majeed
Siddiqui
Department of Mathematics, Pennsylvania State University, York Campus, 1031 Edgecomb Avenue, York, PA 17403, USA
55-67
Numerical Study of Thermosolutal Convection in Anisotropic Porous Media Subject to Cross-Fluxes of Heat and Mass
In this paper, we present a numerical study of an anisotropic porous medium where we analyze double-diffusive natural convection in a square cavity filled with porous media that is subject to uniform heat flux along vertical walls and a solutal flux along horizontal surfaces. The formulation of the problem is based on the Darcy−Brinkman model. The density variation of the saturating fluid is taken into account by the Boussinesq approximation. The system of the coupled equations is solved by the classic finite volume method.
The effect of anisotropy in permeability is analyzed through the terms of the average heat and mass transfer on the vertical and horizontal walls of the cavity, respectively. We realized that the results depend on several characteristic parameters, and general correlations are established for the calculation of heat and mass transfer, according to various studied parameters. According to the buoyancy ratio, we found three distinct regimes: thermal convective, diffusive, and intermediate. The transition from one regime to another is strongly affected by the permeability anisotropy. The effects of porous thermal Rayleigh and Lewis numbers are investigated for different values of permeability ratio characteristic of the anisotropy of porous media.
F.
Oueslati
LETTM, Dépt. de Physique, Faculté des Sciences de Tunis, 2092 El Manar Tunis, Tunisia
Habib
Sammouda
Higher School of Science and Technology of Hammam Sousse- Sousse university- Tunisia
Ali
Belghith
Faculte des Sciences de Tunis, Laboratoire des Transferts de Chaleur et de Masse, Campus Universitaire, 1060 Tunis, Tunisia
69-82
Experimental and Numerical Investigation of Solute Diffusion through Porous Media
The diffusion of solutes in the environment tends to deviate from Fickian assumptions at higher solute concentrations. In order to understand the degree of deviation in the diffusive transport of species, diffusion experiments through porous media using sodium chloride is conducted. The results obtained from the experiments showed a linear relationship between chloride diffusivity and square root value of chloride concentration. The relevance of diffusion coefficient function in the transport studies is also established using numerical simulation studies involving diffusion coefficient function and diffusion coefficient at infinite dilution.
K. Prabhakaran
Nair
Department of Mechanical Engineering, National Institute of Technology Calicut, Calicut, Kerala, India
A.
Praveen
Department of Civil Engineering, Rajiv Gandhi Institute of Technology, Kottayam, Kerala 686, 501, India
83-92