Begell House
Journal of Porous Media
Journal of Porous Media
1091-028X
13
4
2010
KINETIC STUDY FOR THE ADSORPTION OF ACATONE AND ETHANOL ON ACTIVATED CARBON
Gas adsorption in a microporous solid takes place in three locations: the micropores, the mean pores, and the exterior surface of solid grains. Usually, the mathematical description of the kinetics of such a phenomenon needs a detailed preliminary study of the physical and chemical properties of the adsorbent-adsorbate pair. This article proposes a new mathematical model for the study of the adsorption kinetics. In such a model, the adsorbent-adsorbate system is assumed to be a black box, where we know only the adsorbate instantaneous quantities at the input and the output as well as the used adsorbent mass. This model presents some advantages as it contains only three constants to be determined experimentally. It does not require the chemical and the physical properties of the adsorbent-adsorbate pair, and the phenomenon is described by only one differential equation. This is due to the introduction of two new terms in Tick's law, which are justified by the application conditions of such a law and which are not verified in the case of the gas adsorption in a microporous solid. The first term added is a direct adsorption term corresponding to adsorption in the mean or large pores and to the outward surface. As for the second term, it corresponds to the fluctuation defining the transportation phenomenon presented in classical physics.
Mhiri
Foued
Institut prÃ©paratoire aux Ã©tudes dâ€™ingÃ©nieur de Monastir
Abdelmajid
Jemnia
Laboratoire d'Etude des Systemes Thermiques et Energetiques, Ecole Nationale d'Ingenieurs de Monastir, Tunisia
295-305
RADIAL VIBRATIONS OF THICK-WALLED HOLLOW POROELASTIC CYLINDERS
A study of the radial vibrations of hollow poroelastic cylinders of infinite extent is made following Biot's theory of wave propagation in liquid-filled porous media. The frequency equations of these vibrations for a permeable and an impermeable surface are derived. Two limiting cases of ratio of wall thickness to inner radius of the hollow poroelastic cylinder are considered, namely, when these ratios are very small and very large. The first limiting case corresponds to modes of a thin poroelastic shell and plate, while in the second limiting case, modes of a poroelastic solid cylinder and poroelastic bore in an infinite poroelastic medium are obtained. Plots of nondimensional frequency as a function of ratio of wall thickness to inner radius are presented for a permeable and an impermeable surface and are then discussed. By ignoring the liquid effects, the results of a purely elastic solid are obtained as a special case.
M.
Tajuddin
Department of Mathematics, Osmania University, Hyderabad - 500 007 (AP) India
S. Ahmed
Shah
Department of Mathematics, Deccan College of Engineering and Technology, Hyderabad - 500 001 (AP) India
307-318
PERMEABILITY ESTIMATION OF NANO-POROUS MEMBRANES FOR NONWETTING FLUIDS
The permeability behavior of nanoporous membranes is investigated. A novel data reduction scheme for extrusion porometry is used to obtain a statistically based pore size distribution from the porometer flow data. The permeability is calculated from the distribution and constituent properties of the membrane/resin interactions. The study characterizes a commercially available extended polytetrafluoroethylene membrane and evaluates the effective permeability based on the membrane properties, contact angle between the wetting fluid and membrane, and applied pressure. A sensitivity analysis shows that in the case of nonwetting fluids the membrane permeability is not a material constant, but varies as a function of the selected fluid and process pressure.
Solange C.
Amouroux
Center for Composite Materials, and Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
Dirk
Heider
Center for Composite Materials, and Department of Electrical and Computer Engineering, University of Delaware, Newark, Delaware 19716, USA
John W.
Gillespie Jr.
Center for Composite Materials, Department of Materials Science and Engineering, Department of Civil and Environmental Engineering, University of Delaware, Newark, DE 19716, USA
319-329
THERMAL-DIFFUSION AND DIFFUSION-THERMO EFFECTS ON MIXED CONVECTION HEAT AND MASS TRANSFER IN A POROUS MEDIUM
The thermal-diffusion and diffusion-thermo effects on free convection heat and mass transfer, over an infinite vertical plate with periodic temperature and concentration variation, have been studied. The fluid under consideration is obeying the rheological equation of state due to Walter's stress-strain relation. The governing equations have been solved by the use of Laplace transform and the perturbation scheme. The velocity, temperature, and concentration distribution are obtained. The Nusselt number, Nu, and Sherwood number, Nm, are also obtained. The effects of various physical parameters acting on the problem are discussed by a set of figures in a quantitative illustration.
Sallam N.
Sallam
Mathematics Department, Faculty of Education, Ain Shams University, Heliopolis, Cairo, Egypt
331-345
MHD VISCOUS FLOW OVER A LINEARLY STRETCHING SHEET EMBEDDED IN A NON-DARCIAN POROUS MEDIUM
A non-similarity solution of the laminar viscous flow of an electrically conducting fluid over a linearly stretching sheet embedded in a non-Darcian porous medium with a transverse magnetic field is obtained. The Adomian-Pad? approach is employed to solve the differential equations subject to the transformed initial conditions. In particular, both cases of impermeable and permeable horizontal surfaces are examined. The graphical results of the velocity profiles for selected values of the parameters are presented.
349-355
EXPLICIT ANALYTICAL SOLUTION FOR A MODIFIED MODEL OF SEEPAGE FLOW WITH FRACTIONAL DERIVATIVES IN POROUS MEDIA
In this paper, we investigate the seepage flow problem of non-Newtonian fluids through a porous medium. The pressure fields of flow through a porous medium of a non-Newtonian fluid with fractional derivative model are described by fractional partial differential equations. A kind of powerful analytical method, called Homotopy Perturbation Method (HPM) is also introduced to obtain the exact solutions of the problem. The objective is to propose alternative method of solution, which does not require small parameters, avoid linearization and physically unrealistic assumptions. The results show that the proposed method is very efficient and convenient and can readily be applied to a large class of problems.
A.
Sadighi
Department of Mechanical Engineering, Babol University of Technology, P. O. Box 484, Babol, Iran
Davood D.
Ganji
Department of Mechanical Engineering, Babol University of Technology, Babol, Iran
M.
Esmaeilpour
Department of Mechanical Engineering, Babol University of Technology, Iran
357-364
WATER TABLE FLUCTUATIONS IN A SLOPING AQUIFER: ANALYTICAL EXPRESSIONS FOR WATER EXCHANGE BETWEEN STREAM AND GROUND-WATER WITH SURFACE INFILTRATION
This paper presents an analytical solution of a linearized Boussinesq's equation to obtain exact expressions for hydraulic head and flow rate in an unconfined downward sloping aquifer. The aquifer is in contact with a constant piezometric head at the left boundary and a stream at the right boundary whose water level is rising at a constant rate. The aquifer also receives a constant vertical recharge from the land surface due to rain infiltration. The governing equation is solved analytically using the Laplace transform to obtain the expressions for hydraulic head and flow rate. The proposed analytical solutions are verified with an earlier known solution for a horizontal aquifer with zero surface infiltration and found to be in complete agreement. The combined effect of slope and recharge on water table fluctuation and flow rate is studied by considering a numerical example. Model results establish the dependence of the water table fluctuations and flow rate on bed slope and surface recharge rate. The analytical expressions derived here can also represent an asymptotic scenario of either sudden rise or very slow rise in the stream water.
Rajeev K.
Bansal
Department of Mathematics, University of Pune, India
Samir K.
Das
Department of Computational Fluid Dynamics, International Institute of Information Technology, P-14, Rajiv Gandhi Infotech Park, Hinjawadi, Pune- 411057, India
365-374
A NUMERICAL ANALYSIS OF THERMAL CONDUCTIVITY, THERMAL DISPERSION, AND STRUCTURAL EFFECTS IN THE INJECTION PART OF THE RESIN TRANSFER MOLDING PROCESS
Thermal conductivity, thermal dispersion, and structural effects in resin transfer molding (RTM) process are studied numerically. The injection part of the RTM process is modeled as a transport of resin flow through a fibrous porous medium in a long rectangular channel. The fluid flow is modeled using the Darcy-Brinkman-Forchheimer model and the heat transfer process using the energy equation based on local thermal equilibrium assumption. Both isotropic and anisotropic heat transfer in porous media are investigated. The governing equations are solved numerically for the isotropic heat transfer case and analytically for the anisotropic case. The numerical results are fitted to the available experimental data with at most 3% discrepancy, and the effective thermal conductivity of the fibrous porous medium is estimated. Taking into account the quadratic dependency of dispersion conductivity on Peclet number, the Chang model is recommended for the prediction of stagnant thermal conductivity as well as a correlation for dispersion conductivity. Finally, the effects of structural parameters on temperature distribution and velocity profiles are investigated.
Mohammad
Layeghi
Department of Wood & Paper Science & Technology, University of Tehran; and School of Mechanical Engineering, Sharif University of Technology, Iran
Mohammad
Karimi
Sharif University of Technology, Iran
Hamid Reza
Seyf
Department of Mechanical and Aerospace Engineering, University of Missouri, Columbia, Missouri 65211, USA
375-385
FLOW AND HEAT TRANSFER ALONG AN INFINITE HORIZONTAL POROUS PLATE THROUGH A POROUS MEDIUM IN A ROTATING SYSTEM
An exact solution of the flow and heat transfer along an infinite horizontal porous plate embedded in porous medium in a rotating system has been obtained. It is found that the boundary layer thickness increases with increase in permeability of the porous medium. It is also found that the critical Eckert number for which there is no flow of heat either from the plate to the fluid or from fluid to plate decreases with increase in the permeability of the porous medium.
Mrinmoy
Guria
Department of Applied Mathematics with Oceanology and Computer Programming, Vidyasagar University, Midnapore - 721102, West Bengal, India
G.
Manna
Department of Applied Mathematics with Oceanology and Computer Programming, Vidyasagar University, Midnapore-721 102, West Bengal, India
387-393
Third International Conference on Porous Media and its Applications in Science, Engineering and Industry, June 20-24, 2010, Tuscany, Italy
Third International Conference on Porous Media and its Applications in Science, Engineering and Industry
Sponsored by Engineering Conferences International & U.S. National Science Foundation
June 20-24, 2010, Tuscany, Italy
Synopsis
We had organized and held two highly successful conferences on Porous Media and its Applications in Science, Engineering and Industry were held in 1996 in Kona, Hawaii, and in 2007 in Kauai, Hawaii, which were attended by various researchers in porous media worldwide. This conference will build on the last two conferences so that it reflects the research done internationally in the currently active areas of the topic. The presence of the highly successful Journal of Porous Media and both editions of the very well received Handbook of Porous Media will act as an additional impetus to further galvanize this conference. Papers of high quality will be considered for submission to the Journal of Porous Media.
Preliminary Conference Outline
1. Natural And Forced Convection In Porous Media
2. Evaporation, Condensation, Capillary Effects And Reactive Flow In Porous Media
3. Radiation Heat Transfer In Porous Media
4. Conduction in Porous Media
5. Combined Heat and Mass Transfer in Porous Media
6. Particle Transport and Deformable Porous Bodies
7. Advanced Mathematical Approaches to the Modeling of Porous Media
8. Industrial and Environmental Heat Transfer and Flow in Porous Media
9. Process Heat Transfer
10. Advances in Numerical Techniques
11. Experimental and Measuring Techniques
12. Turbulence in Porous Media
13. Particle Migration and Deposition in Porous Media
14. Bio Transport in Porous Media
15. Material Processing Applications
395-399