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porous-media
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Criteria for Local Thermal Equilibrium in Forced Convection in Channel Filled by Porous Medium
, M.Sc. Thesis Sharif University of Technology ; Nori Brojerdi, Ali (Supervisor)
Abstract
Forced convection in a parallel plate channel filled by porous medium, with walls held at constant heat flux is investigated. A criterion for employing a local Thermal Equilibrium assumption between solid matrix and fluid in a porous channel is developed. Darcy-Brinkman-Forchheimer momentum equation is solved by Homotopy perturbation method. The energy equation for solid and fluid phases employing Local Thermal Non Equilibrium (LTNE) assumption is solved for fully developed and thermally developing forced convection. The analysis leads to an expression for fluid and solid temperatures and also the local Nusselt number. The effect of pertinent parameters such as the Darcy number, the Inertia...
Modeling of Deposition of Low Density Lipoprotein (LDL) in Carotid Artery
, M.Sc. Thesis Sharif University of Technology ; Saeedi, Mohammad Saeed (Supervisor)
Abstract
Atherosclerosis is one of the most important and common causes of death in the world. Atherosclerosis typically affects medium and large arteries in the body and it leads to plaque formation in arterial wall. The first stage of plaque formation has been related to accumulation of low density lipoproteins in arterial wall.
The purpose of this research is presenting a four-layer model to describe the LDL transport in the arterial wall. The endothelium, intima, internal elastic lamina (IEL) and media are all treated as macroscopically homogeneous porous media and the volume-averaged porous media equations are employed to model various layers. The physiological parameters within the various...
The purpose of this research is presenting a four-layer model to describe the LDL transport in the arterial wall. The endothelium, intima, internal elastic lamina (IEL) and media are all treated as macroscopically homogeneous porous media and the volume-averaged porous media equations are employed to model various layers. The physiological parameters within the various...
Simulation of Residual Oil Displacement at the Pore-scale
, M.Sc. Thesis Sharif University of Technology ; Moosavi, Ali (Supervisor) ; Shafii, Mohammad Behshad (Supervisor)
Abstract
EOR (oil enhanced recovery) is very important as oil is a nonrenewable resource. Depending on the characteristics of the rock formation, primary production can result in the recovery of up to 20% of the oil originally in the rock. This means that at least 80% of the oil may remain in the rock unless additional technology is used to increase the recovery. Before finding best way to do for EOR, scientists must study properties of different porous media that oil is trapped between its grains. Most of research and studies investigate networks of porous media but this work focused on oil movement through a pore space in porous media lonely not in network by waterflooding. Studying a pore space is...
Numerical Modeling of Porous Burner
, M.Sc. Thesis Sharif University of Technology ; Saeedi, Mohammad Saeed (Supervisor) ; Saeedi, Mohammad Hassan (Supervisor)
Abstract
Porous burner technology has many advantages in comparison with conventional burners such as higher burner thermal performance, lower pollutants emission, high power ranges, fuel flexibility, compact geometry and higher turn down ratios. These kinds of burners are made of preheated porous combustion zone and combustion porous zone that have different thermophysical and geometrical properties. In this work, the transient one-dimensional multi-step premixed laminar reacting flows in a two-stage porous media burner have been investigated. The combustible mixture is considered H2-Air (9 species and 19 reactions) and CH4-Air (22 species and 49 reactions). In porous media, without lateral wall...
Experimental and Modeling Study of Enhanced Oil Recovery Improvement during Nanosilica Particle Flooding to Oil Reservoirs
, M.Sc. Thesis Sharif University of Technology ; Vosoughi, Manuchehr (Supervisor) ; Ghazanfari, Mohammad Hassan (Supervisor) ; Masihi, Mohsen (Supervisor)
Abstract
Recent studies in nanotechnology field have shown this technology could solve many challenges and needs in oil and gas industry. As yet, many applications of nanoparticles in enhanced oil recovery have been reported. One of the most important applications is wettability alteration due to presence of nanoparticles in injecting fluid, which has recently been studied by several research groups. These studies indicate that, presence of nanoparticles in injecting water would improve oil recovery. However, there is no adequate information about the mechanisms affecting fluid flow in reservoir rock and its mathematical modeling.The aim of this project is to evaluate the effect of injection of...
Experimental Study of Nano-bio Material Injection for Heavy Oil Recovery in Shaly Systems Using Micro-model Apparatus
, M.Sc. Thesis Sharif University of Technology ; Vossoughi, Manouchehr (Supervisor) ; Ghazanfari, Mohammad Hossein (Co-Advisor)
Abstract
In this research we aim to find enhance oil recovery mechanisms involved in nano-bio material injection by micro model apparatus which has not been studied before. Especially for injection in heavy oil and shaly porous media that forms most of heavy oil reservoirs. To this end, microscopic images from injection of nano-bio materials to shaly patterns have been taken and analyzed to find the process mechanism. Also amount of enhance oil recovery in different conditions like type of microbe forming bio material, nano-bio material concentration and type of flow pattern (shale characteristics including length, direction and distance from injection and production wells) will be studied.Three...
Experimental Investigation of Asphaltic Sludge Formation Caused by Asphaltenic Oil Carbonated Reservoir Acid Stimulation
, Ph.D. Dissertation Sharif University of Technology ; Ghotbi, Cyrus (Supervisor) ; Ayatollahi, Shahab (Supervisor)
Abstract
Acidizing is one of the most effective techniques to remove the formation damage and restore (or even increase) the permeability of the near wellbore region. Although this technique is widely used to resolve the skin problem, it could initiate new damages itself that hinder the fluid flow and decrease the well production, consequently. Acid-oil emulsion and sludge formation are known as two major induced formation damage and the main reasons for the oil well acid treatment failures.When the HCl is reacted with asphaltenic crude oil during matrix acidizing, it results in unexpected damage at the near wellbore region and hinder the fluid flow through certain mechanisms include:
1- Pore...
1- Pore...
MultiScale Pore Network Modeling to be Compared with Experimental Results
, M.Sc. Thesis Sharif University of Technology ; Ayatollahi, Shahab (Supervisor) ; Jamshidi, Saeed (Supervisor) ; Kazemzadeh, Ezatollah (Supervisor)
Abstract
The study of porous media, especially in pore-scales (micro and nano scales), is of particular importance in various sciences such as petroleum engineering, chemical, and civil engineering. Determine the physics of the pore scale to understand it better, identify the conditions for it to enforce the laws better, and explain some of the phenomena unknown so far, and finally obtain the parameters performed in the laboratory for specific samples are the main goals of these studies. One of the most well-known methods for analyzing porous media is pore network modeling. These models are always affected by the macroscopic structure of porous media, such as their multiscale state. In this study, an...
Numerical Study of Heat Transfer Enhancement in Porous Medium by Applying Magnetic Field on Nano Fluid
, M.Sc. Thesis Sharif University of Technology ; Sadrhosseini, Hani (Supervisor)
Abstract
A 2D simulation has been carried out to study the effect of magnetic field on heat transfer and pressure drop of nanofluid flowing through a pipe filled with porous medium. The nanofluid flow is modeled as a single-phase flow, and Darcy–Brinkman–Forchheimer equation is employed to model fluid flow in porous media. A constant uniform heat flux was imposed on the walls of the cylinder, and the values of Darcy number, Hartmann number, and volume fraction of the nanoparticles were selected as 0.1, 200, and 0.2, respectively. Effects of parameters such as Reynolds number, the material of the porous medium (conductivity and porosity), and material of nanofluids have been investigated in the...
Evaluation the Effect of Molecular-Structural Properties of Asphaltene Fraction on Wettability Alteration and Crude Oil Dynamic Flow in Porous Media
, M.Sc. Thesis Sharif University of Technology ; Taghikhani, Vahid (Supervisor) ; Shahrabadi, Abbas (Co-Supervisor) ; Naderi, Hassan (Co-Supervisor) ; Taheri Shakib, Jaber (Co-Supervisor)
Abstract
In order to investigate the effect of molecular-structural properties of asphaltene fraction on changes in wettability and flow of crude oil in the porous medium, four crude oil samples from oil fields in southern Iran were tested ;To know the characteristics of crude oil, molecular-structural properties of asphaltene fraction and the effect of asphaltene fraction on the wettability properties of surface, Experiments such as crude oil density and viscosity measurement, crude oil hydrocarbon analysis, asphaltene extraction with standard IP-143 method, elemental analysis and metal content, gel permeation chromatography, nuclear magnetic resonance, interaction between rock and asphaltene....
A new scaling relationship for water imbibition into the matrix: Considering fracture flow
, Article Energy Sources, Part A: Recovery, Utilization and Environmental Effects ; Vol. 36, issue. 12 , Dec , 2010 , p. 1267-1275 ; ISSN: 15567036 ; Shadizadeh, S. R ; Masihi, M ; Sharif University of Technology
Abstract
Spontaneous imbibition of water into the matrix is the most important mechanism for oil recovery in water wet fractured porous media. If the water is in contact with matrix and it is not flowing, the process is called static imbibition. The effect of rock and fluid properties, and boundary conditions on static imbibition are studied and formulated for scaling of the laboratory data to the reservoir scale. In reality, there is a continuous flow in a fracture; incorporating the effect of fracture flow into the scaling formulations is an unresolved issue in the modeling of the capillary imbibition recovery from the matrix. In this article, a new mathematical equation is developed to scale...
Scaling equations for oil/gas recovery from fractured porous media by counter-current spontaneous imbibition: From development to application
, Article Energy and Fuels ; Vol. 27, issue. 8 , July , 2013 , p. 4662-4676 ; ISSN: 08870624 ; Masihi, M ; Sharif University of Technology
Abstract
Spontaneous imbibition, the capillary-driven process of displacing the nonwetting phase by the wetting phase in porous media, is of great importance in oil/gas recovery from matrix blocks of fractured reservoirs. The question of how properly scaling up the recovery by counter-current spontaneous imbibition has been the subject of extensive research over decades, and numerous scaling equations have been proposed. As a convention, the scaling equations are usually defined analytically by relating the early time squared recovery to squared pore volume. We show this convention does not apply to common scaling practices and, if used, causes nontrivial scatter in the scaling plots. We explain that...
Numerical investigation of nanofluid mixed-convection flow in the entrance region of a vertical channel partially filled with porous medium
, Article Heat Transfer - Asian Research ; Vol. 43, issue. 7 , November , 2014 , p. 607-627 ; Dehkordi, A. M ; Jamshidi, S ; Sharif University of Technology
Abstract
In this article, transient two-dimensional mixed convection of nanofluids in the entrance region of a vertical channel has been studied carefully. The geometry under consideration consisted of a parallel-plate channel partly filled with a porous medium with a constant wall temperature. In the free flow region, the two-dimensional flow field has been governed by the Navier-Stokes equations. The general formulation of the momentum equations accounting for the inertial and the viscous effects in the presence of a porous medium has been used. Viscous dissipation effects have also been incorporated in the thermal energy equation. Effects of Brownian diffusion and thermophoresis have also been...
Scaling equations for oil/gas recovery from fractured porous media by counter-current spontaneous imbibition: From development to application
, Article Energy and Fuels ; Volume 27, Issue 8 , 2013 , Pages 4662-4676 ; 08870624 (ISSN) ; Masihi, M ; Sharif University of Technology
2013
Abstract
Spontaneous imbibition, the capillary-driven process of displacing the nonwetting phase by the wetting phase in porous media, is of great importance in oil/gas recovery from matrix blocks of fractured reservoirs. The question of how properly scaling up the recovery by counter-current spontaneous imbibition has been the subject of extensive research over decades, and numerous scaling equations have been proposed. As a convention, the scaling equations are usually defined analytically by relating the early time squared recovery to squared pore volume. We show this convention does not apply to common scaling practices and, if used, causes nontrivial scatter in the scaling plots. We explain that...
Monitoring and characterizing the finger patterns developed by miscible displacement in fractured heavy oil systems
, Article Industrial and Engineering Chemistry Research ; Volume 52, Issue 31 , July , 2013 , Pages 10853-10863 ; 08885885 (ISSN) ; Majidi, S. M. J ; Ghazanfari, M. H ; Sharif University of Technology
2013
Abstract
This work concerns experimentally quantifying finger behavior during miscible displacements in fractured porous media. A series of miscible tests were performed on five-spot fractured micromodels which were initially saturated with heavy crude oil, and the developed finger patterns were quantified using an image analysis technique. The results revealed that the numbers of macro fingers formed is well correlated with the square root of dimensionless time, while the rate of finger initiation is independent of fracture characteristics. The level of bypassed oil linearly decreases with dimensionless distance traveled by front precisely. The transient fractal dimension behavior experiences a...
Modeling of cohesive crack growth in partially saturated porous media; A study on the permeability of cohesive fracture
, Article International Journal of Fracture ; Volume 167, Issue 1 , Jan , 2011 , Pages 15-31 ; 03769429 (ISSN) ; Khoei, A. R ; Mofid, M ; Sharif University of Technology
Abstract
Modeling the water flow in cohesive fracture is a fundamental issue in the crack growth simulation of cracked concrete gravity dams and hydraulic fracture problems. In this paper, a mathematical model is presented for the analysis of fracture propagation in the semi-saturated porous media. The solid behavior incorporates a discrete cohesive fracture model, coupled with the flow in porous media through the fracture network. The double-nodded zero-thickness cohesive interface element is employed for the mixed mode fracture behavior in tension and contact behavior in compression. The modified crack permeability is applied in fracture propagation based on the data obtained from experimental...
Extended finite element modeling of deformable porous media with arbitrary interfaces
, Article Applied Mathematical Modelling ; Volume 35, Issue 11 , 2011 , Pages 5426-5441 ; 0307904X (ISSN) ; Haghighat, E ; Sharif University of Technology
Abstract
In this paper, an enriched finite element method is presented for numerical simulation of saturated porous media. The arbitrary discontinuities, such as material interfaces, are encountered via the extended finite element method (X-FEM) by enhancing the standard FEM displacements. The X-FEM technique is applied to the governing equations of porous media for the spatial discretization, followed by a generalized Newmark scheme used for the time domain discretization. In X-FEM, the material interfaces are represented independently of element boundaries and the process is accomplished by partitioning the domain with some triangular sub-elements whose Gauss points are used for integration of the...
Experimental investigation of nano-biomaterial applications for heavy oil recovery in shaly porous models: A pore-level study
, Article Journal of Energy Resources Technology, Transactions of the ASME ; Volume 137, Issue 1 , August , 2014 ; 01950738 (ISSN) ; Ghazanfari, M. H ; Vossoughi, M ; Sharif University of Technology
American Society of Mechanical Engineers (ASME)
2014
Abstract
Application of nano or biomaterials for enhanced oil recovery (EOR) has been recently much attended by petroleum engineering researchers. However, how would be the displacement mechanisms and how would change the recovery efficiency while nano and biomaterials are used simultaneously is still an open question. To this end, a series of injection tests performed on micromodel containing shale strikes. Three types of biomaterials including biosurfactant, bioemulsifier, and biopolymer beside two types of nanoparticles including SiO2 and TiO2 at different concentrations were used as injection fluids. The microscopic as well as macroscopic efficiency of displacements were observed from analysis of...
Modeling fluid flow under sonic wave field in fractured porus media-with an approach to capillary forces
, Article 4th International Conference and Exhibition: New Discoveries through Integration of Geosciences, 5 April 2010 through 8 April 2010 ; 2010 ; Ghazanfari, M ; Ghotbi, C ; Kharrat, R ; Sharif University of Technology
European Association of Geoscientists and Engineers, EAGE
Abstract
Till now, no mathematical model is presented to model the flow under sonic field be applied in fractured reservoirs. This will be more noticeable when we bear in mind that several reservoirs in Middle East region are fractured. In this work the effects of elastic waves on capillary trapping and mobility of Bingham plastic fluids in fractures have been investigated. Eventually, a model for predicting the influence range of the wave in fractured reservoirs is presented. The results of this study clarified that radiation of wave with low frequency and intensity extremely increases the flow rate and decreases the minimum pressure gradient required for flow of Bingham plastic fluids in fractured...
Percolation-based effective permeability estimation in real heterogeneous porous media
, Article 15th European Conference on the Mathematics of Oil Recovery, 29 August 2016 through 1 September 2016 ; 2016 ; 9462821933 (ISBN); 9789462821934 (ISBN) ; Gago, P ; King, P ; DCSE; Schlumberger; Shell ; Sharif University of Technology
European Association of Geoscientists and Engineers
Abstract
It has long been understood that flow behavior in heterogeneous porous media is largely controlled by the continuity of permeability contrasts. With this in mind, we are looking in new methods for a fast estimation of the effective permeability which concentrates on the properties of the percolating cluster. From percolation concepts we use a threshold permeability value (Kth) by which the gridblocks with the highest permeability values connect two opposite side of the system in the direction of the flow. Those methods can be applied to heterogeneous media of a range of permeabilities distribution and various underlying structures. We use power law relations and weighted power averages that...