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porous-media
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Effect of Kinetic and Hydrodynamic on Asphaltene Deposition in Porous Media
, Ph.D. Dissertation Sharif University of Technology ; Rashtchian, Davoud (Supervisor) ; Jamialahamdi, Mohammad (Supervisor) ; Tohidi, Bahman (Supervisor)
Abstract
Asphaltene are the heaviest components if some crude oil which are in thermodynamic equilibrium. Any change in the equilibrium condition including change in temperature, pressure or composition may render asphaltene to come out of solution and precipitate. Asphaltene precipitation and deposition is one of the main problems in some of the oil fields. Precipitated asphaltene may deposit in the reservoir, near wellbore, wellstring, transport pipeline and surface facilities. In porous media, the deposited asphaltene over the surface and/or across pore throat can severely reduce the effective permeability and results in decreasing of the oil production. Also, the deposited asphaltene results in...
Hydro-mechanical modeling of cohesive crack propagation in multiphase porous media using the extended finite element method
, Article International Journal for Numerical and Analytical Methods in Geomechanics ; Volume 37, Issue 10 , July , 2013 , PP. 1247–1279 ; Khoei, A. R. (Amir Reza) ; Sharif University of Technology
Abstract
In this paper, a numerical model is developed for the fully coupled hydro-mechanical analysis of deformable, progressively fracturing porous media interacting with the flow of two immiscible, compressible wetting and non-wetting pore fluids, in which the coupling between various processes is taken into account. The governing equations involving the coupled solid skeleton deformation and two-phase fluid flow in partially saturated porous media including cohesive cracks are derived within the framework of the generalized Biot theory. The fluid flow within the crack is simulated using the Darcy law in which the permeability variation with porosity because of the cracking of the solid skeleton...
Random walk simulation of miscible flow through heterogeneous 2D porous media considering dispersion tensor
, Article Chemical Engineering Science ; Volume 132 , August , 2015 , Pages 81-92 ; 00092509 (ISSN) ; Ghazanfari, M. H ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
Most of numerical approaches describing the behavior of miscible displacement in porous media through the solution of advection-dispersion equation suffer from numerical dispersion. Random Walk (RW) method is a good candidate to overcome this problem especially in heterogeneous media. In addition, how treating dispersion coefficient as a tensor might affect the accuracy of RW simulation results is not well understood. Here, a RW model was developed and used for simulating miscible displacement experiments performed on heterogeneous micromodels including single fracture/flow barrier. Dispersion coefficient was treated as a tensor and a hybrid scheme was used for velocity interpolation. The...
A bridge between dual porosity and multiscale models of heterogeneous deformable porous media
, Article International Journal for Numerical and Analytical Methods in Geomechanics ; Volume 43, Issue 1 , 2019 , Pages 212-238 ; 03639061 (ISSN) ; Khoei, A. R ; Sharif University of Technology
John Wiley and Sons Ltd
2019
Abstract
In this paper, a multiscale homogenization approach is developed for fully coupled saturated porous media to represent the idealized sugar cube model, which is generally employed in fractured porous media on the basis of dual porosity models. In this manner, an extended version of the Hill-Mandel theory that incorporates the microdynamic effects into the multiscale analysis is presented, and the concept of the deformable dual porosity model is demonstrated. Numerical simulations are performed employing the multiscale analysis and dual porosity model, and the results are compared with the direct numerical simulation through 2 numerical examples. Finally, a combined multiscale-dual porosity...
A bridge between dual porosity and multiscale models of heterogeneous deformable porous media
, Article International Journal for Numerical and Analytical Methods in Geomechanics ; Volume 43, Issue 1 , 2019 , Pages 212-238 ; 03639061 (ISSN) ; Khoei, A. R ; Sharif University of Technology
John Wiley and Sons Ltd
2019
Abstract
In this paper, a multiscale homogenization approach is developed for fully coupled saturated porous media to represent the idealized sugar cube model, which is generally employed in fractured porous media on the basis of dual porosity models. In this manner, an extended version of the Hill-Mandel theory that incorporates the microdynamic effects into the multiscale analysis is presented, and the concept of the deformable dual porosity model is demonstrated. Numerical simulations are performed employing the multiscale analysis and dual porosity model, and the results are compared with the direct numerical simulation through 2 numerical examples. Finally, a combined multiscale-dual porosity...
Hybrid finite volume-finite element methods for hydro-mechanical analysis in highly heterogeneous porous media
, Article Computers and Geotechnics ; Volume 132 , 2021 ; 0266352X (ISSN) ; Ataie Ashtiani, B ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
In this study, two classes of advanced finite volume schemes, including Multi-Point Flux Approximation (MPFA) and Dual Discrete Finite Volume (DDFV) method, have been employed in conjunction with the finite element (FE) geomechanics simulator to model the coupled fluid-solid system. Fully saturated porous media with poroelastic behavior, random field permeability and elastic modulus are considered as parameters. The performance of the proposed hydro-mechanical models, including MPFA O-FEM and DDFV-FEM, is examined through different test cases. First, the models are validated and compared with the closed-form solutions in the homogeneous domain. Second, the methods' stability and convergence...
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,...
Study of Capillary Pressure Effect on Multiphase Flow in Hydrocarbon Reservoirs
, M.Sc. Thesis Sharif University of Technology ; Taghizadeh Manzari, Mehrdad (Supervisor)
Abstract
One of the most important issues in the petroleum industry, is how to increase the oil production from hydrocarbon reservoirs. The optimum design of an enhanced oil recovery process needs the knowledge on the physical phenomena of the working flow in oil reservoirs. An important aspect of any oil recovery process is the effectiveness of process fluid in removing oil from the rock pores at microscopic scales, in a way that it determines the success or failure of the recovery process. Meanwhile, one of the most important factors on the fluid mobility and as a result the microscopic mobility efficiency is the pressure difference between different phases in narrow paths of porous media. This...
Pore Network Model of Two Phase Flow in low permeable carbonate Rock
, Ph.D. Dissertation Sharif University of Technology ; Bozorgmehry, Ramin (Supervisor) ; Pishvaie, Mahmoud Reza (Supervisor)
Abstract
Development of pore network models for real porous media requires a detailed understanding of physical processes occurring on the microscopic scale and a complete description of porous media morphology. In this study, the microstructure of porous media has been represented by three dimensional networks of interconnected pores and throats which are designed by an object oriented approach. Afterwards, the connectivity of the system has been optimized by an optimization algorithm. To validate the methodology, a network of a carbonate sample is constructed. In this model, the geometrical characteristics of the pores and throats, such as their shapes, effective radii and lengths, are selected...
Evaluation of RANS Models for Turbulent Flow in Porous Media
, M.Sc. Thesis Sharif University of Technology ; Kazemzadeh Hannani, Siamak (Supervisor) ; Mozaffari, Ali Asghar (Co-Advisor)
Abstract
Lamniar flow through porous media has been investigated using finite volume staggered grid. In order to study turbulent flow modelling turbulent flow using RANS models with the aid of Fluent software has been done. And the microscopic and macroscopic results are compared with LES results. None of the RANS models used (k-e, RNG, k-wv2f, v2f and RSM) were able to model the flow through porous media properly, although k-e and RSM gave the best microscopic and macroscopic results
Evaluation of using Lattice Boltzmann Method for Simulation of Two Phase Flow in Saturated Porous Media
, M.Sc. Thesis Sharif University of Technology ; Pak, Ali (Supervisor)
Abstract
Fluid flow in porous media is a common phenomenon in the nature, in many fields of science and engineering such as flow of water in the soil, migration of contaminants in the soil, petroleum reservoir engineering, semi?olten magma flow in the crust, water flow in plants, blood flow in body tissues, etc. In many cases, the porous structure of the medium and fluid flow pattern are very complex because of the inherent problems of fluidAluid and fluidsolid interactions. Also, secondary issues such as intrinsic permeability and tortuosity of porous media, and relative permeability of two phase flow, increase the complication of the analyses. Studying these types of phenomena in the nature or even...
Heat Transfer Enhancement in Shell-and-Tube Heat Exchangers Using Porous Media
, M.Sc. Thesis Sharif University of Technology ; Farhanieh, Bijan (Supervisor) ; Afshin, Hossein (Supervisor)
Abstract
Heat transfer enhancement in heat transfer equipment, such as heat exchangers, has been widely studied. There are plenty of techniques to increase heat transfer in tubular heat exchangers. One of these techniques is applying a porous medium. These media have a great interface with fluids which can enhance the heat transfer rate. Meanwhile, the thermal conductivity of these media is usually greater than that of the studied fluid. Thus, by adding a kind of highly conductive porous insert to a heat exchanger, we are able to save the material used to construct the device and the space occupied by it.
Shell-and-tube heat exchangers are one of the most widely-used types of exchangers in...
Shell-and-tube heat exchangers are one of the most widely-used types of exchangers in...
Performance of Partially Filled Mini-Channels with Porous Media
, M.Sc. Thesis Sharif University of Technology ; Nouri, Ali (Supervisor) ; Moosavi, Ali (Co-Advisor)
Abstract
Laminar forced convection flow through a channel partially filled with a porous material was numerically studied in this thesis. The Navier-Stokes and Brinkman-Forchheimer equations were used to model the fluid flow in the free and porous regions, respectively. Coupling of the pressure and velocity fields was resolved using the SIMPLEC algorithm. The local thermal equilibrium was adopted in the energy equation. The effects of the thermal conductivity ratio, Darcy number, porosity, Reynolds number and height of the porous insert on velocity and temperature field were investigated. The results show that the flow behavior and its associated heat transfer are susceptible to the variation of the...
Qualitative Simulation of Fluid Flow in Reservoir Using Fuzzy Logic
, M.Sc. Thesis Sharif University of Technology ; Pishvaie, Mahmoud Reza (Supervisor) ; Jamshidi, Saeed (Supervisor)
Abstract
Investigation of reservoir performance and long-term production prediction are main goal of numerical simulation. Numerical simulation mainly consists of solving sets of non-linear equations developed by combination of continuity equation, equation of state and Darcy equation. Classical methods such as finite difference method (FDM), finite volume method (FVM) and finite element method (FEM) are widely used for solving sets of fluid flow equations that mentioned above. Researchers have used other methods like boundary element method recently. Each of these methods has their own restrictions. But the main source of error in these methods is due to numerical estimation of spatial derivatives...
Investigation of Resin Flow in Vacuum Infusion Process (VIP)
, M.Sc. Thesis Sharif University of Technology ; Seif, Mohammad Saeed (Supervisor)
Abstract
The use of Vacuum Infusion Process (VIP) in some industries , to achieve optimal injection strategy is based on trial and error and it comes to the production of defective and unusable parts.The main problem is that no resin penetrate in some areas and creat dry spots and unsaturated resin regions Because of inadequate or incorrect positioning of the resin inlet and air outlet.Simulation is a powerful tool for understanding and identifying the behavior of resin flow and thereby save time and cost.In this research,in order to avoid the empirical testing of different injection techniques and avoid wasting time and cost in traditional methods of trial and error,the use of vacuum...
Wettability Altration Determination by Using Streaming Potential
, M.Sc. Thesis Sharif University of Technology ; Massihi, Mohsen (Supervisor) ; Ayatollahi, Shahabodin (Supervisor)
Abstract
The assessment of fluid transport in porous media is the main subject in oil reservoirs to understand the oil recovery efficiency. The efficiency of Enhanced oil recovery (EOR) processes depends on the surface properties and wetting behavior of oil reservoir rocks which are also affected by the electrokinetic behavior of solid part of the porous rock. Streaming potential measurement is one of the techniques to determine the electrokinetic properties. The streaming potential measurements using electrodes have recently been introduced in oil field applications and there are still significant uncertainties during the measurements and interpretation of streaming potential results. The Primarily...
An Investigation on the Effects of Porous Media on Propagation of Aero-acoustic Waves, Using LBM
,
M.Sc. Thesis
Sharif University of Technology
;
Tayyebi Rahni, Mohammad
(Supervisor)
;
Massah, Hamid Reza
(Co-Advisor)
Abstract
With advances in technology, production and propagation of sound waves in the air has become very important. One of the main goals of study of these waves is controlling them. The environment plays the most important role in sound propagation. Therefore, the properties of the environment and their effects should be studied. One such concern studied widespread previously, is porosity and porous media effects on the properties of a fluid flow and sound waves through it. An important application of this study is sound proofing systems. In this project two-dimensional numerical simulation of aeroacoustic waves passing through a porous media is carried out, using Lattice Boltzmann Method. The aim...
Experimental Study of Internal Forced Convection of Ferrofluid Flow in Porous Media
, M.Sc. Thesis Sharif University of Technology ; Sadrhosseini, Hani (Supervisor) ; Shafii, Mohammad Behshad (Co-Advisor)
Abstract
The present work illustrates the results of an experimental study of ferrofluid flow in a tube subjected to a constant heat flux on its wall and filled with permeable material under the effect of magnetic field. The aim of this project is investigating the enhancement of heat transfer and obtaining a uniform temperature distribution inside the pipe. In order to achieve this, a porous medium with a porosity of 0.39 and ferrofluid with volume fractions of 0.6, 1.0 and 1.5 are used simultaneously, in the presence of magnetic field. The experiments are held for four different Reynolds numbers of 147.1, 167.3, 184.3 and 205.1. Also, four various modes of the oscillatory magnetic field are applied...
Experimental Investigation of Effect of Nanoparticles on Fines Migration Control in Porous Media
, M.Sc. Thesis Sharif University of Technology ; Ghazanfari, Mohammad Hossein (Supervisor) ; Taghikhani, Vahid (Supervisor)
Abstract
Fines migration due to their severe problems during oil production must be controlled. They cause the productivity decline due to their deposition near the well bore. Recently, application of nanotechnology in fine migration control has been much attended in both experimental and field case investigations. The main goal of the present study is to find out the ability and different effects of Nano particles (NPs) such as concentration, types and even the magnetic sensitivity to retain fines migration. In order for this, two groups of tests were conducted by engineered porous media. In this study, for the first time, an experimental setup was designed and constructed to investigate the control...
Mixed Convection of Magnetic Nanofluids in Channels Filled with a Porous Medium in the Presence of External Magnetic Field
, Ph.D. Dissertation Sharif University of Technology ; Molaei, Asghar (Supervisor) ; Shahrokhi, Mohammad (Supervisor)
Abstract
In this research work, mixed convection heat transfer of ferrofluids (i.e., magnetite nanoparticle) in a circular pipe fully filled with a porous medium in the presence of constant and alternating magnetic fields has been investigated both numerically and experimentally. The duct was heated by a heating coil and the magnetic field was applied via four electromagnets with U shaped ferrite cores and a frequency inverter. The nanoparticles were synthesized using co-precipitation method and coated with a surfactant (i.e., Tween 80) and doubled distilled water was used as the base fluid. To characterize the synthesized nanoparticles, various analyzing techniques such as VSM, SEM, and XRD were...