Begell House
Journal of Porous Media
Journal of Porous Media
1091-028X
13
11
2010
SMOOTHED PARTICLE HYDRODYNAMICS SIMULATION OF EFFECTIVE THERMAL CONDUCTIVITY IN POROUS MEDIA OF VARIOUS PORE STRUCTURES
Heat conduction through a 2−D porous medium layer with complicated cylindrical or quadrangular pore structures is simulated using the smoothed particle hydrodynamics technique. Heat transfer paths are visualized at the micropore level, and the dependence of the effective thermal conductivity on the micropore structure is analyzed. As expected, heat always follows the path of least resistance through the porous structures. Globally, enhanced heat transfer paths tend to form in the porous medium having the smallest circular inclusions. The dependence of the effective thermal conductivity on the micropore structure is found to be closely related to the formation of enhanced heat transfer paths. For the porous medium with dispersed pore phase, the inclusion shape and size and the relative arrangement between inclusions do not have any particular effect on the relation between the effective thermal conductivity and the porosity. This finding is also well predicted by the effective medium theoretical (EMT) model with a flexible factor within the range 4.0−4.5. Owing to the significant effect of the pore-phase distribution, for the porous medium with continuous pore phase, the relation between the effective thermal conductivity and porosity can be predicted using the EMT model only if the flexible factor is taken for a value of 3.5.
Antonio C. M.
Sousa
Departamento de Engenharia Mecânica; Universidade de Aveiro;Campus Universitário de Santiago; 3810-193 Aveiro-Portugal; and Department of Mechanical Engineering; University of New Brunswick; Fredericton, NB, Canada E3B 5A3
Fangming
Jiang
Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, No.2 Nengyuan Rd., Tianhe District, Guangzhou 510640, China; Penn. State Univeristy
951-960
THE PERFORMANCE OF POLYMER FLOODS IN PARTIALLY FRACTURED RESERVOIRS
With the growing demand for oil and the prospect of higher prices, the application of enhanced oil recovery (EOR) processes is becoming an important strategy for many oil-producing companies around the world, including in the Middle East region. In this region, there are a large number of oil and gas reservoirs that are naturally fractured. In fact, most hydrocarbon reservoirs are fractured to some degree. Among EOR processes, polymer flooding represents an attractive option that could be applied in many of these reservoirs. Therefore understanding what parameters affect polymer flooding in naturally fractured reservoirs and their impact on performance prediction is critical in the decision on the applicability of this recovery technique. Using fine-mesh numerical reservoir simulations, this study investigated the performance of polymer floods in fully to slightly fractured reservoirs. A random distribution of fractures was assumed to simulate the irregularity of typical fracture networks. A dual-porosity, dual-permeability model was used to simulate the displacement phenomena. Extensive simulation runs were performed to determine the functional relationship between recovery performance and various design parameters during polymer flooding. These parameters included (1) fracture intensity; (2) well configurations; (3) polymer slug size; and (4) polymer concentration. Results show that these parameters have significant effects on the efficiency of a polymer flood. A critical value of fracture intensity appears to delineate favorable from unfavorable performance in polymer floods. The ranges for the values of parameters under which polymer floods may yield better performance are presented.
Abdullah F.
Alajmi
Petroleum Engineering Department, College of Engineering & Petroleum, Kuwait University
Ridha B.
Gharbi
Department of Petroleum Engineering, College of Engineering & Petroleum, Kuwait University, P. O. Box 5969, Safat 13060, Kuwait
Robert
Chase
Department of Petroleum Engineering, Marietta College, Marietta, OH 45750
961-971
THIN FILM FLOW OF A NON-NEWTONIAN FLUID DOWN A VERTICAL CYLINDER THROUGH A POROUS MEDIUM
This article investigates the thin film flow of an Oldroyd-8 constant fluid through a porous medium. The fluid considered here is electrically conducting, and a constant pressure gradient is applied for the flow phenomena. The governing nonlinear problem has been solved analytically by the homotopy analysis method. The graphical results are presented to gauge the effects of certain physical parameters and to show the convergence of the results.
Sohail
Nadeem
Department of Mathematics, Quaid-i-Azam University 45320, Islamabad 44000, Pakistan
M.
Awais
Department of Mathematics, Quaid-i-Azam University, Islamabad 44000
973-980
CROSS-FLOW HEAT EXCHANGER EMBEDDED WITHIN A POROUS MEDIUM
The present work examines numerically the cross-flow and heat transfer from a bundle of staggered cylinders embedded in a porous medium. The effects of Reynolds number within the laminar flow regime, permeability, and thermal conductivity of the porous material on the fluid flow and heat transfer from the cylinders in the cross-flow are examined. Also, the results are compared with heat transfer from a cylinder embedded in a porous medium. Prandtl number is fixed to 1.0 for gases. It is found that the porous medium may enhance the rate of heat transfer if the permeability of the porous material is high, that is, the Darcy number is greater than 10−3. Also, increasing the thermal conductivity of the porous material has a positive effect on enhancing the rate of heat transfer from the single column of cylinders or from the cylinders in the first column of a multicolumn heat exchanger. However, the porous medium may have a negative effect on the rate of heat transfer from downstream cylinders, where the temperature gradient decreases because of the enhanced rate of heat transfer from the upstream cylinders.
L. B.
Younis
SNC-Lavalin Inc, Calgary, Alberta, T2P 3H5, Canada
981-988
VISCOUS DISSIPATION EFFECT ON NATURAL CONVECTION IN A FLUID SATURATED POROUS MEDIUM
This paper considers the problem of viscous dissipation effects on non-Darcy natural convection over a vertical flat plate embedded in a fluid-saturated porous medium. Forchheimer extension is considered in the flow equations and its contribution to viscous dissipation is considered in the energy equation. The nondimensional governing equations are solved, numerically, by the finite-element method (FEM). The resulting nonlinear integral equations are linearized and solved using Newton-Raphson iterations. Numerical results for the details of the stream function, velocity and temperature contours, and profiles as well as heat transfer rates in terms of the Nusselt number, are presented in graphs.
Mohamed F.
El-Amin
Mathematics Department, Aswan Faculty of Science, South Valley University, Aswan, 81258; King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia
Amgad
Salama
King Abdullah University of Science and Technology (KAUST), Kingdom of Saudi Arabia; Nuclear Research Center, AEA, Abu Zabal, Egypt
Ibrahim
Abbas
Mathematics Department, Sohag Faculty of Science, South Valley University, Sohag
989-997
COUETTE FLOW OF AN OLDROYD-B FLUID WITH SLIP CONDITION
This investigation analyzed the influence of slip condition on the rotating and magnetohydrodynamic (MHD)flow of an Oldroyd-B fluid filling the porous space between the two plates. The lower plate was fixed while the upper one oscillated in its own plane. Based on modified Darcy's law, the governing problem was solved analytically. The derived solutions are discussed quantitatively with respect to the various parameters embedded in the system.
Tasawar
Hayat
Department of Mathematics, Quaid-I-Azam University 45320, Islamabad 44000, Pakistan; Nonlinear Analysis and Applied Mathematics (NAAM) Research Group, Faculty of Science,
King Abdulaziz University, Jeddah 21589, Saudi Arabia
Saher
Najam
Department of Mathematics, Quaid-i-Azam University 45320, Islamabad 44000, Pakistan
Chaudry Masood
Khalique
Department of Mathematical Sciences, International Institute for Symmetry Analysis and Mathematical Modelling, North West University, Mmabatho 2735, South Africa
999-1006
DRAG ON A POROUS SPHERE EMBEDDED IN ANOTHER POROUS MEDIUM
This article concerns the solution of the problem of an incompressible viscous fluid flow past a porous sphere embedded in another porous medium. The Brinkman equations for the flow inside and outside the porous sphere in their stream function formulations are used. Explicit expressions of the stream functions and shear stresses for inside and outside flow fields are obtained. The drag force experienced by a porous sphere embedded in another porous medium is also evaluated. The dependence of the drag coefficient and the shearing stress on permeability for a porous sphere is presented graphically and analytically. Special well-known results are then deduced from the analysis.
Satya
Deo
Department of Mathematics, University of Allahabad, Allahabad 211 002, India
Baliram R.
Gupta
Department of Mathematics, Jaypee University of Engineering and Technology, Raghogarh, Guna - 473226 (MP), India
1009-1016
MASS TRANSFER IN WOOD: IDENTIFICATION OF STRUCTURAL PARAMETERS FROM DIFFUSIVITY AND PERMEABILITY MEASUREMENTS
This article proposes a rapid way to use experimental measurements of mass transferminus;mass diffusivity and permeability to air−to compute two global morphological parameters of wood: tortuosity factor and equivalent pore radius. The device conceived for measuring mass diffusing in steady state is a specific vaporimeter PVC-CHA. For air permeability, another device, ALU-CHA, has been developed. Using a simple structure modeling of the porous medium to analyze the transport phenomena, the two global morphologic parameters cited have been fitted. Spruce, pine, beech, and teak are tested through samples (about 24) of these species, sawed for longitudinal, tangential, and radial directions flows. Some of the measurements are exploited. The results obtained for tortuosity and equivalent pore radius have been compared with those found in the anatomical literature, and a good concordance has been observed.
Patrick
Perre
Laboratoire d'Etudes et Recherche sur le Matériau Bois L.E.R.Ma.B., ENGREF, 54042 Nancy Cedex, France
Eusebe
Agoua
Laboratoire dâ€™EnergÃ©tique et de MÃ©canique AppliquÃ©e (LEMA/EPAC/UAC)
1017-1024
NONSIMILAR SOLUTIONS FOR MIXED CONVECTION OF WATER AT 4° C OVER A VERTICAL SURFACE WITH PRESCRIBED SURFACE HEAT FLUX IN A POROUS MEDIUM
In this study, the mixed convection of water at 4°C along a vertical plate with prescribed surface heat flux in a porous medium is investigated numerically using the implicit finite difference method. Nonsimilar solutions are obtained for both forced convection- and free convection-dominated regimes. The velocity and temperature profiles are shown to explain the flow as well as temperature variation as a function of controlling parameters. Skin friction and Nusselt number are obtained and compared with the available numerical results for various values of different parameters. Several values of the heat flux variation parameter λ and mixed convection parameter ξ, are considered for the purpose of comparison of skin friction and heat transfer results.
Waqar A.
Khan
Department of Engineering Sciences, PN Engineering College, National University of Sciences and Technology, Karachi; CHASHMA Nuclear Power Plant, Pakistan Atomic Energy Commission, Mianwai, Pakistan
Rama Subba Reddy
Gorla
Department of Mechanical Engineering, Cleveland State University, Cleveland, OH, 44115 USA
1025-1032
SECOND-GRADE MAGNETOHYDRODYNAMIC FLUID FLOW IN POROUS MEDIA
We introduce the magnetohydrodynamic equations of a second-grade, non-Newtonian, incompressible, two-dimensional fluid flow in a porous medium. Exact solutions are discussed when the particular form of the stream function is in terms of the unknown function with the exponential factor that gives the reversed and nonreversed flows. The results are compared with the existing second-grade and Newtonian flows.
Muhammad Raheel
Mohyuddin
COMSATS Institute of Information Technology, Abbottabad, Pakistan; Department of Physics, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45195, Iran
S.
Islam
Department of Mathematics, COMSATS Institute of Information Technology, Chakshazad Park Road, Islamabad, Pakistan
Akhtar
Hussain
Department of Mathematics, COMSATS Institute of Information Technology, Chakshazad Park Road, Islamabad, Pakistan
A. M.
Siddiqui
Department of Mathematics, Pennsylvania State University, York Campus, 1031 Edgecomb Avenue, York, PA 17403, USA
1033-1037