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porous-medium
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Vorticity-based coarse grid generation for upscaling two-phase displacements in porous media
, Article Journal of Petroleum Science and Engineering ; Volume 59, Issue 3-4 , 2007 , Pages 271-288 ; 09204105 (ISSN) ; Firoozabadi, B ; Mahani, H ; Khoozan, D ; Sharif University of Technology
2007
Abstract
Coarse grid generation from finely gridded geological model is a main step in reservoir simulation. Coarse grid generation algorithms aim at optimizing size, number and location of the grid blocks by identifying the important geological and flow features which control flow in porous media. By optimizing coarse grid structure we can improve accuracy of the coarse scale simulation results to reproduce fine grid behavior. A number of techniques have been proposed in the literature. We present a novel coarse grid generation procedure based on vorticity preservation between fine and coarse grids. In the procedure, the coarse grid mesh tries to capture variations in both permeability and fluid...
Onset of convection in a horizontal porous channel with uniform heat generation using a thermal nonequilibrium model
, Article Transport in Porous Media ; Volume 69, Issue 3 , 2007 , Pages 343-357 ; 01693913 (ISSN) ; Noghrehabadi, A. R ; Rees, D. A. S ; Sharif University of Technology
2007
Abstract
This paper considers the onset of free convection in a horizontal fluid-saturated porous layer with uniform heat generation. Attention is focused on cases where the fluid and solid phases are not in local thermal equilibrium, and where two energy equations describe the evolution of the temperature of each phase. Standard linearized stability theory is used to determine how the criterion for the onset of convection varies with the inter-phase heat transfer coefficient, H, and the porosity-modified thermal conductivity ratio, γ. We also present asymptotic solutions for small values of H. Excellent agreement is obtained between the asymptotic and the numerical results. © Springer...
The effect of local thermal non-equilibrium on conduction in porous channels with a uniform heat source
, Article Transport in Porous Media ; Volume 69, Issue 2 , 2007 , Pages 281-288 ; 01693913 (ISSN) ; Noghrehabadi, A. R ; Rees, D. A. S ; Sharif University of Technology
2007
Abstract
We examine the effect of local thermal non-equilibrium on the steady state heat conduction in a porous layer in the presence of internal heat generation. A uniform source of heat is present in either the fluid or the solid phase. A two-temperature model is assumed and analytical solutions are presented for the resulting steady-state temperature profiles in a uniform porous slab. Attention is then focussed on deriving simple conditions which guarantee local thermal equilibrium. © Springer Science+Business Media, Inc. 2006
Experimental and modelling study of gravity drainage in a three-block system
, Article Transport in Porous Media ; Volume 136, Issue 2 , 2021 , Pages 471-494 ; 01693913 (ISSN) ; Karimi Malekabadi, A ; Ghazanfari, M. H ; Rostami, B ; Sharif University of Technology
Springer Science and Business Media B.V
2021
Abstract
Gravity drainage is known as the controlling mechanism of oil recovery in naturally fractured reservoirs. The efficiency of this mechanism is controlled by block-to-block interactions through capillary continuity and/or reinfiltration processes. In this study, at first, several free-fall gravity drainage experiments were conducted on a well-designed three-block apparatus and the role of tilt angle, spacers’ permeability, wettability and effective contact area (representing a different status of the block-to-block interactions between matrix blocks) on the recovery efficiency were investigated. Then, an experimental-based numerical model of free-fall gravity drainage process was developed,...
Computational homogenization of fully coupled multiphase flow in deformable porous media
, Article Computer Methods in Applied Mechanics and Engineering ; Volume 376 , April , 2021 ; 00457825 (ISSN) ; Saeedmonir, S ; Sharif University of Technology
Elsevier B. V
2021
Abstract
In this paper, a computational modeling tool is developed for fully coupled multiphase flow in deformable heterogeneous porous medium that consists of complex and non-uniform micro-structures using the dual continuum scales based on the computational homogenization approach. The first-order homogenization technique is employed to perform the multi-scale analysis. The governing equations of two-phase flow of immiscible fluids, including an equilibrium equation and two mass continuity equations, are considered based on the appropriate main variables. According to the well-known Hill–Mandel principle of macro-homogeneity, the proper energy types are defined instead of conventional stress power...
Investigation on reactive flow through porous media by quadtree Lattice Boltzmann
, Article Journal of Natural Gas Science and Engineering ; Volume 104 , 2022 ; 18755100 (ISSN) ; Ayatollahi, S ; Jamshidi, S ; Raoof, A ; Sharif University of Technology
Elsevier B.V
2022
Abstract
In this study, in order to investigate the effect of the underlying pore-scale processes on continuum scale simulations of porous media dissolution, we improve the standard Lattice Boltzmann method using Quadtree grid refinement approach to simulate fluid flow and reactive transport through large domain sizes. Our results have shown considerable computational improvements up to 80% in simulation time together with increased numerical accuracy. The results and the added value of the new approach are discussed using comparison of our model with the conventional LBM. Moreover, we have applied a systematic analysis by increasing complexity levels and starting from fluid flow and continuing with...
Thermal and hydraulic performance of rectangular microchannel heat sinks with trapezoidal porous configuration
, Article Numerical Heat Transfer; Part A: Applications ; Volume 81, Issue 3-6 , 2022 , Pages 72-93 ; 10407782 (ISSN) ; Vafai, K ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
In this article, the thermal and hydraulic capacity of a rectangular microchannel heat sink with different trapezoidal porous configuration’s inlet heights (Formula presented.) and outlet heights (Formula presented.) are examined. A three-dimensional model is used for microchannels with miscellaneous trapezoidal porous configuration’s inlet and outlet heights, and the laminar fluid flow and conjugate heat transfer equations are numerically solved. Darcy-Brinkmen-Forchheimer equation is utilized for transport through the porous region. For microchannels with miscellaneous porous distribution’s inlet and outlet heights, the Nusselt number, pressure drop and figure of merit (FOM), a criterion...
Impact of swimming gyrotactic microorganisms and viscous dissipation on nanoparticles flow through a permeable medium: a numerical assessment
, Article Journal of Nanomaterials ; Volume 2022 , 2022 ; 16874110 (ISSN) ; Younis, J ; Ali, K ; Rizwan, M ; Ashraf, M ; Abd El Salam, M. A ; Sharif University of Technology
Hindawi Limited
2022
Abstract
In this paper, heat and mass transportation flow of swimming gyrotactic microorganisms (microbes) and solid nanoparticles under the viscous dissipation effect is investigated. The flow model PDEs are renovated with ordinary ones using suitable boundary layer approximations. The system governing the flow model dimensionless equations as well as boundary conditions is numerically treated with the SOR (successive over relaxation) technique. The flow, heat, and mass transport characteristics are examined against the prime parameters. A comparison is examined to be in a good agreement with the earlier results. It is found here that flow and thermal characteristics of the problem are substantially...
A numerical analysis of thermal conductivity, thermal dispersion, and structural effects in the injection part of the resin transfer molding process
, Article Journal of Porous Media ; Volume 13, Issue 4 , 2010 , Pages 375-385 ; 1091028X (ISSN) ; Karimi, M ; Seyf, H. R ; Sharif University of Technology
2010
Abstract
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...
DNAPL flow and complex electrical resistivity evolution in saturated porous media: A coupled numerical simulation
, Article Journal of Contaminant Hydrology ; Volume 248 , 2022 ; 01697722 (ISSN) ; Deparis, J ; Leroy, P ; Ataie Ashtiani, B ; Davarzani, H ; Colombano, S ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Induced Polarization (IP) is a non-intrusive geophysical method to monitor Dense Non-Aqueous Phase Liquid (DNAPL) contamination and remediation processes underground. In this study, an advanced numerical code simulating DNAPL flow and complex electrical resistivity is presented. The model was validated against existing IP results and image measurements that were carried out previously in a series of 2D tank experiment. Multiphase flow modeling in porous media is coupled with electrical current modeling to simulate the process of DNAPL migration and the associated IP response. This brings a broader view of the contamination in space and time compared to surface and borehole measurements,...
Modelling of power-law fluid flow through porous media using smoothed particle hydrodynamics
, Article Transport in Porous Media ; Volume 74, Issue 3 , 2008 , Pages 331-346 ; 01693913 (ISSN) ; Manzari, M. T ; Sharif University of Technology
2008
Abstract
The flow of non-Newtonian fluids through two-dimensional porous media is analyzed at the pore scale using the smoothed particle hydrodynamics (SPH) method. A fully explicit projection method is used to simulate incompressible flow. This study focuses on a shear-thinning power-law model (n < 1), though the method is sufficiently general to include other stress-shear rate relationships. The capabilities of the proposed method are demonstrated by analyzing a Poiseuille problem at low Reynolds numbers. Two test cases are also solved to evaluate validity of Darcy's law for power-law fluids and to investigate the effect of anisotropy at the pore scale. Results show that the proposed algorithm can...
An automated simple algorithm for realistic pore network extraction from micro-tomography images
, Article Journal of Petroleum Science and Engineering ; Vol. 123, issue , 2014 , pp. 164-171 ; ISSN: 09204105 ; Jamshidi, S ; Salehi, S
Abstract
Using 3-D scanned data to analyze and extract pore network plays a vital role in investigation of porous media's characteristics. In this paper, a new simple method is developed to detect pores and throats for analyzing the connectivity and permeability of the network. This automated method utilizes some of the common and well-known image processing functions which are widely accessible by researchers and this has led to an easy algorithm implementation. In this method, after polishing and quality control of images, using city-block distance function and watershed segmentation algorithm, pores and throats are detected and 3-D network is produced. This method can also be applied on 2-D images...
Electrokinetic mixing and displacement of charged droplets in hydrogels
, Article Transport in Porous Media ; Vol. 104, Issue. 3 , Jun , 2014 , pp. 469-499 ; ISSN: 01693913 ; Sharif University of Technology
Abstract
Mixing in droplets is an essential task in a variety of microfluidic systems. Inspired by electrokinetic mixing, electric field-induced hydrodynamic flow inside a charged droplet embedded in an unbounded polyelectrolyte hydrogel is investigated theoretically. In this study, the polyelectrolyte hydrogel is modeled as a soft, and electrically charged porous solid saturated with a salted Newtonian fluid, and the droplet is considered an incompressible Newtonian fluid. The droplet-hydrogel interface is modeled as a surface, which is located at the plane of shear, with the electrostatic potential ζ. The fluid inside the droplet attains a finite velocity owing to hydrodynamic coupling with the...
A coupled hydro-mechanical analysis for prediction of hydraulic fracture propagation in saturated porous media using EFG mesh-less method
, Article Computers and Geotechnics ; Vol. 55, issue , January , 2014 , p. 254-266 ; Pak, A ; Soga, K ; Sharif University of Technology
Abstract
The details of the Element Free Galerkin (EFG) method are presented with the method being applied to a study on hydraulic fracturing initiation and propagation process in a saturated porous medium using coupled hydro-mechanical numerical modelling. In this EFG method, interpolation (approximation) is based on nodes without using elements and hence an arbitrary discrete fracture path can be modelled.The numerical approach is based upon solving two governing partial differential equations of equilibrium and continuity of pore water simultaneously. Displacement increment and pore water pressure increment are discretized using the same EFG shape functions. An incremental constrained Galerkin...
Experimental and numerical investigation of polymer flooding in fractured heavy oil five-spot systems
, Article Journal of Petroleum Science and Engineering ; Volume 108 , 2013 , Pages 370-382 ; 09204105 (ISSN) ; Ghazanfari, M. H ; Masihi, M ; Rashtchian, D ; Sharif University of Technology
2013
Abstract
Microscopic and macroscopic displacements of polymer flooding to heavy oil at various levels of salinity and connate water saturation have been investigated. Both oil-wet and water-wet conditions in fractured five-spot micromodel systems, initially saturated with the heavy crude oil are utilized. The primary contribution is to examine the role of salinity, wettability, connate water, and fracture geometry in the recovery efficiency of the system. The microscopic results revealed that the increase in the connate water saturation decreases the oil recovery, independent of the wettability conditions. Moreover, the increase in salinity of the injected fluids lowers the recovery efficiency due to...
Effects of viscoelastic polymer solutions on the oil extraction from dead ends
, Article Scientia Iranica ; Volume 20, Issue 6 , 2013 , Pages 1912-1920 ; 2345-3605 (e-ISSN) ; Ramazani, A. S. A ; Kamyabi, M. M ; Sharif University of Technology
Sharif University of Technology
2013
Abstract
This research deals with the numerical simulation of two viscoelastic uids ow in an open capillary of a reservoir. Oldroyd-B and Leonov models have been used to describe the rheological behavior of polymer solutions. The finite volume method on a structured and collocated grid has been used for discretization of the governing equations. The discrete elastic viscous stress splitting technique has also been used. The steady state, isothermal and incompressible uids past through a two dimensional micropore have been considered. The numerical method has been validated through the comparison of numerical results by the analytical solutions of Oldroyd-B uid ow through a planar channel. The effects...
Transient behavior of fluid flow and heat transfer in vertical channels partially filled with porous medium: Effects of inertial term and viscous dissipation
, Article Energy Conversion and Management ; Volume 61 , September , 2012 , Pages 1-7 ; 01968904 (ISSN) ; Molaei Dehkordi, A ; Sharif University of Technology
Elsevier
2012
Abstract
In this article, transient hydrodynamic and heat-transfer behavior of Newtonian fluid flow in vertical parallel-plate channels partially filled with a porous medium has been investigated numerically. In this regard, the influences of macroscopic local inertial term and the viscous heating due to the viscous dissipation were taken into account in the momentum equations of porous region and the thermal energy equations, respectively. Moreover, Forchheimer-Brinkman extended Darcy model was used to model fluid flow in the porous region. In addition, an analytical solution was obtained in the case of negligible Brinkman and Forchheimer number values at the steady-state conditions. The predicted...
Analysis of nanofluid heat transfer in parallel-plate vertical channels partially filled with porous medium
, Article International Journal of Thermal Sciences ; Volume 55 , 2012 , Pages 103-113 ; 12900729 (ISSN) ; Molaei Dehkordi, A ; Sharif University of Technology
Abstract
In this article, mixed-convective heat transfer of nanofluids in a vertical channel partially filled with highly porous medium was studied. In the porous region, the Brinkman-Forchheimer extended Darcy model was used to describe the fluid flow pattern. Different viscous dissipation models were also applied to account for viscous heating. At the porous medium-fluid interface, interfacial coupling conditions for the fluid velocity and temperature were used to derive the analytical solution using a two-parameter perturbation method. The model used for the nanofluids incorporates the effects of Brownian motion and thermophoresis. With constant wall temperature, velocity and temperature profiles...
Permeability impairment study due to asphaltene deposition: experimental and modeling approach
, Article Transport in Porous Media ; Volume 91, Issue 3 , February , 2012 , Pages 999-1012 ; 01693913 (ISSN) ; Ghoodjani, E ; Sharif University of Technology
2012
Abstract
This fact is well known that during any scenario of production, asphaltene deposition in porous media has a substantial effect on oil flow. But a clear understanding of asphaltene deposition mechanisms can help to minimize asphaltenic problem in oil-bearing formations. In this study, the experimental results of three dynamic CO 2 miscible injection tests were investigated. Regarding the effects of adsorption, mechanical entrapment, and sweeping mechanisms on permeability behavior, a mathematical mass and permeability variation model were developed. According to the experimental results asphaltene deposition causes a 70% loss of sand stone initial permeability while the loss is significantly...
Experimental investigation of the asphaltene deposition process during different production schemes
, Article Oil and Gas Science and Technology ; Volume 66, Issue 3 , 2011 , Pages 507-519 ; 12944475 (ISSN) ; Kharrat, R ; Ghotby, C ; Sharif University of Technology
2011
Abstract
Experimental Investigation of the Asphaltene Deposition Process during Different Production Schemes - This paper presents the results of asphaltene precipitation and deposition during lean gas injection, CO2 injection and natural depletion in reservoir conditions. In addition, the effect of variations in operating pressure, injection gas concentration and production rate on asphaltene precipitation and deposition were investigated. The severity of asphaltene deposition was found to be more pronounced in lean gas injection in comparison with CO2 injection and natural depletion. Increasing the flow rate in natural depletion xperiments showed a considerable increase in asphaltene deposition,...