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Invasion percolation in presence of gravity
, Article Iranian Journal of Chemistry and Chemical Engineering ; Vol. 29, issue. 1 , 2010 , p. 71-82 ; ISSN: 10219986 ; Masihi, M ; Sharif University of Technology
Abstract
Simultaneous capillary dominated displacement of the wetting and non-wetting phases are processes of interest in many disciplines including modeling of the penetration of polluting liquids in hydrology or the secondary migration in petroleum reservoir engineering. Percolation models and in particular invasion percolation is well suited to characterize the slow immiscible displacement of two fluids when both the gravity and viscous effects are negligible. In particular, the characteristic of the percolating cluster and the other important percolation properties at the breakthrough can be inferred. However, with the inclusion of the gravity forces, the behavior may change. For example, as the...
The impact of silica nanoparticles on the performance of polymer solution in presence of salts in polymer flooding for heavy oil recovery
, Article Fuel ; Vol. 123 , May , 2014 , pp. 123-132 ; ISSN: 00162361 ; Kharrat, R ; Mohebbi, A ; Ghazanfari, M. H ; Sharif University of Technology
Abstract
Due to role of polymer in increasing sweep efficiency during oil recovery, much attention has been paid to the using polymer solutions in enhanced oil recovery methods. In spite of the existence of the great researches in this area, the role of nanoparticles in modification of the polymer performance in the presence of salts has not been examined before. Furthermore, there is no information about how the dispersed silica nanoparticles affect the heavy oil recovery during the polymer flooding in the presence of divalent cations. In this study, a series of polymer flooding experiments are performed in a quarter five-spot glass micromodel saturated with heavy oil. Solutions of polyacrylamide...
Invasion percolation in presence of gravity
, Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 29, Issue 1 , 2010 , Pages 71-82 ; 10219986 (ISSN) ; Masihi, M ; Sharif University of Technology
2010
Abstract
Simultaneous capillary dominated displacement of the wetting and non-wetting phases are processes of interest in many disciplines including modeling of the penetration of polluting liquids in hydrology or the secondary migration in petroleum reservoir engineering. Percolation models and in particular invasion percolation is well suited to characterize the slow immiscible displacement of two fluids when both the gravity and viscous effects are negligible. In particular, the characteristic of the percolating cluster and the other important percolation properties at the breakthrough can be inferred. However, with the inclusion of the gravity forces, the behavior may change. For example, as the...
Permeability correlation with porosity and Knudsen number for rarefied gas flow in Sierpinski carpets
, Article Journal of Natural Gas Science and Engineering ; Volume 56 , 2018 , Pages 549-567 ; 18755100 (ISSN) ; Salimi, M. R ; Taeibi Rahni, M ; Sharif University of Technology
Elsevier B.V
2018
Abstract
In recent years, application of porous media is highlighted among researchers due to their wide range of usability in micro-scale problems, such as gas reservoirs, micro-filtering, heat exchangers, etc. With this respect, the accurate description of flow behavior using governing equations based on the continuum assumption is not valid since the mean free path is comparable to the characteristics length of the problem. For this purpose, a simple methodology for diffusion reflection boundary condition is developed and validated for two valuable benchmarks, namely micro-channel flow and fractal porous media, where the results were in good agreement with literature. Then, pore-scale simulation...
Gas-liquid membrane contactors: Modeling study of non-uniform membrane wetting
, Article Journal of Membrane Science ; Volume 555 , 2018 , Pages 463-472 ; 03767388 (ISSN) ; Mousavi, S. A ; Bozarjomehri, R. B ; Bakhtiari, F ; Sharif University of Technology
Elsevier B.V
2018
Abstract
Current available models for simulation of the separation process in gas-liquid membrane contactor (MC) systems consider a uniform partial membrane wetting along the membrane length (Lmem). However, transmembrane pressure changes along the Lmem. Additionally, the available models usually consider a simplified uniform pore size to represent the micro-porous MC. Additionally, not all pores in a MC have the same size. In this study, a pore-scale network model is developed to simulate the physical separation of H2S using MCs by taking to account for (i) transmembrane pressure variation and (ii) pore size distribution of MC. The model results are compared with the experimental results of H2S...
Computational Simulation of Cooling of Porously Covered Surfaces, Using a Navier-stokes and Lattice Boltzmann Solver
, Ph.D. Dissertation Sharif University of Technology ; Tayyebi Rahni, Mohammad (Supervisor) ; Jam, Freydoon (Co-Advisor)
Abstract
Considering the wide range of applications of porous media for heat transfer enhancement in various components of industrial machineries, including solar collectors, air dryers, compact heat exchangers, electronic microchips, investigation of heat transfer characteristics in porous media has been a major concern for many researchers. On the other hand, precise understanding of the physics of porous media-flow interaction has been an open research topic for a long time. The present research however, has aimed at developing a computational method to simulate the interaction between fluid flow and porous media to investigate heat transfer from prously covered surfaces. Pore scale modeling of...
Pore-scale Simulation of Flow around a Micro-porous Square Cylinder, Using Hybrid LBM-FVM, Considering Slip Condition Inside Porous Media
, M.Sc. Thesis Sharif University of Technology ; Tayyebi Rahni, Mohammad (Supervisor)
Abstract
In recent years, application of porous media is highlighted among researchers due to their wider use in micro-scale problems, such as in gas reservoirs, micro-filtering, and heat exchangers. In such applications, accurate description of flow behavior, using governing equations based on continuum assumption, is not valid, since mean free path has the same order as the characteristic length of the problem. In such cases, imposing appropriate slip condition on the fluid-solid interface of porous media (in pore-scale level), based on kinetics theory, is an appropriate approach. For this purpose, pore-scale simulation of flow inside porous media in slippery and transient regimes is carried out...
Experimental Investigation of Formation Damage Caused by Wellbore Fluids Using Glass Micromodel
, M.Sc. Thesis Sharif University of Technology ; Mahani, Hassan (Supervisor)
Abstract
During all operations in oil and gas reservoirs, it is possible to cause formation damage. These damages can greatly reduce the rate of production. One of the major damages that can seriously affect the performance of a reservoir is the damage caused by drilling fluid. The main purpose of this thesis is to study the main mechanisms of formation damage caused by water-based drilling fluid using a glass micromodel for the first time. An accurate understanding of the mechanisms of formation damage can provide a good understanding of the selection of the type and concentration of materials used, as well as appropriate methods to control and eliminate damages. for controlling the drilling fluid...
Pore-scale simulation of calcite matrix acidizing with hydrochloric acid
, Article SPE Journal ; Volume 26, Issue 2 , 2021 , Pages 653-666 ; 1086055X (ISSN) ; Sharif University of Technology
Society of Petroleum Engineers (SPE)
2021
Abstract
A continuum hydrodynamic model with immersed solid/fluid interface is developed for simulating calcite dissolution by hydrochloric acid (HCl) at the pore scale, and is most accurate for a mass-transfer-controlled dissolution regime under laminar flow conditions. The model uses averaged Navier-Stokes equations to model momentum transfer in porous media and adopts a theoretically developed mass-transfer formulation with assumptions. The model includes no fitting parameter and is validated using experimental results. The findings of previous research and existing models are briefly discussed and their shortcomings and advantages are elucidated. The present model is used in some pore-scale...
Direct insights into the pore-scale mechanism of low-salinity waterflooding in carbonates using a novel calcite microfluidic chip
, Article Fuel ; Volume 260 , 15 January , 2020 ; Mahani, H ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
One of the key open questions in the area of low or controlled salinity water flooding (LSWF or CSWF) is how the observed oil recovery at macro-scale (e.g. Darcy or core-scale) can the explained and what underlying microscopic mechanisms drive it. Thus far, the micromodel investigation of LSWF has been limited to sandstones, remaining challenging to apply to carbonates. In this paper we aim to i) extend the capability to fabricate a novel calcite micromodel using Iceland spar calcite crystal, ii) investigate the pore-scale mechanisms leading to oil recovery from carbonates. A target crude oil-brine-rock (COBR) system was first selected. To screen potential brines which can produce...
Pore Scale Modeling of Gravity Drainage in Fractured Porous Media
, M.Sc. Thesis Sharif University of Technology ; Ghazanfari, Mohammad Hossein (Supervisor)
Abstract
Most of oil content, especially in Iran, has been reserved in fractured reservoirs, so study and modeling of production mechanism of these reservoirs are great of importance. Gravity drainage is one of these effective production mechanisms in fractured porous media which dynamic pore scale modeling of this mechanism will lead to better understanding of it. In this work, the effects of variety of parameters such as oil gravity, interfacial tension between oil and gas, pore and throat size distribution, fracture aperture, and block to block interaction (capillary continuity and reinfiltartion) have been investigated. So developed simulator in this work has two main and separated parts, which...
Pore scale acidizing Simulation Using Lattice Boltzmann Method
, M.Sc. Thesis Sharif University of Technology ; Jamshidi, Saeed (Supervisor)
Abstract
Matrix acidizing aims at bypassing near wellbore damages in typical carbonate reservoirs or enhancing permeability and hydraulic conductivity in naturally fracture ones. The simulation of acidizing process at pore scale and complex geometries by LBM will lead to gain more knowledge about molecular mechanisms that govern rock dissolution, diffusion and advection of reactive fluid and help the evaluation of acidizing efficiency.In this thesis, simulation of acidizing includes the following steps:
• Multicomponent fluid convection
• Fluid diffusion into the solid
• Fluid-rock reaction
• Boundary conditions including periodic, bounceback, non-equilibrium bounceback, Dirichlet,...
• Multicomponent fluid convection
• Fluid diffusion into the solid
• Fluid-rock reaction
• Boundary conditions including periodic, bounceback, non-equilibrium bounceback, Dirichlet,...
Pore-Scale Investigation of the Roles of Oil Types and Pore Structure in Low Salinity Waterfloogin Using Glass Micromodel
, M.Sc. Thesis Sharif University of Technology ; Ayatollahi, Shahabodin (Supervisor) ; Mahani, Hassan (Supervisor)
Abstract
Oil composition plays an undeniable role on the low salinity water flooding (LSWF) efficiency. This property directly affects the kinetics of wettability alteration through electrostatic interactions and interfacial tension (IFT). For instance, mixing in stagnant zones through a thin water film is considered as one of the most important diffusion controlled phenomenon which is goverened by Non-Fickian solute transport model. The major two potentials controlling the solute transport in thin film are salinity gradient and electrostatic potentials, which can be affected by oil composition and surface charges. This study aims to investigate the effect of oil composition on low salinity...
Experimental Investigation of Stimulation Fluid Induced Formation Dmaged Using Micromodel
, M.Sc. Thesis Sharif University of Technology ; Mahani, Hassan (Supervisor) ; Ayatollahi, Shahaboddin (Co-Supervisor)
Abstract
Acidizing as the most frequent stimulation technique in the field, has been extensively used to increase the production rate. Even though acidizing treatments is well established, there is still an inherent risk for self-induced formation damage through incompatibilities of the fluids involved in this process.
A main potential problem during acidizing is the incompatibility of the acid and the reservoir’s crude oil. Acid interaction with crude oil can produce two major damage mechanisms that could offset partially, if not totally the benefit of the acid stimulation. These mechanisms are the rigid film emulsion formation and the acid-sludge precipitation, result in well productivity...
A main potential problem during acidizing is the incompatibility of the acid and the reservoir’s crude oil. Acid interaction with crude oil can produce two major damage mechanisms that could offset partially, if not totally the benefit of the acid stimulation. These mechanisms are the rigid film emulsion formation and the acid-sludge precipitation, result in well productivity...
Lattice Boltzmann Simulation of Fluid Flow Through Porous Media Using Local Grid Refinement
, M.Sc. Thesis Sharif University of Technology ; Jamshidi, Saeed (Supervisor) ; Massihi, Mohsen (Supervisor)
Abstract
In the recent two decades Lattice Boltzmann method has been introduced as a class of computational fluid dynamic methods for fluid simulation. In this method instead of solving Navier-Stocks equation, Boltzmann equation is solved to simulate the flow of a fluid. This method originally was developed based on uniform grids which makes lattice Boltzmann a time consuming technique. This feature already exists in the case of simulation of fluid flow in porous media. To eliminate this limitation some research has been done on methods to formulate lattice Boltzmann on unstructured grids. On the basis of this research a method on non-uniform grids has been selected. Here using object oriented...
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...
Pore-scale modeling of rarefied gas flow in fractal micro-porous media, using lattice Boltzmann method (LBM)
, Article Journal of Thermal Analysis and Calorimetry ; 2019 , Pages 1-12 ; 13886150 (ISSN) ; Salimi, M. R ; Taeibi Rahni, M ; Sharif University of Technology
Springer Netherlands
2019
Abstract
Due to the widespread use of rarefied gas flow in micro-porous media in industrial and engineering problems, a pore-scale modeling of rarefied gas flow through two micro-porous media with fractal geometries is presented, using lattice Boltzmann method. For this purpose, square- and circular-based Sierpinski carpets with fractal geometries are selected due to their inherent behavior for real porous media. Diffusive reflection slip model is used and developed for these porous media through this study. With this respect, the planar Poiseuille flow is selected as a benchmark and validated with the literature. The effect of Knudsen number (Kn) on the permeability is investigated and compared in...
Heat transfer and entropy generation analysis in a three-dimensional impinging jet porous heat sink under local thermal non-equilibrium condition
, Article International Journal of Thermal Sciences ; Volume 153 , 2020 ; Taeibi Rahni, M ; Rostamzadeh, H ; Sharif University of Technology
Elsevier Masson SAS
2020
Abstract
A precise heat transfer simulation of a three-dimensional impinging jet porous heat sink is presented and is analyzed from thermodynamics vantage point under local thermal non-equilibrium condition. To increase the computational efficiency of the analysis, pore-scale modeling based on lattice Boltzmann method (LBM) is used inside the porous media (at a meso-scale), whilst finite volume method (FVM) is employed around it (at a macro-scale). The effects of the Reynolds number, porous layer thickness, solid/fluid thermal conductivity ratio, and porosity on the critical heat transfer and entropy generation parameters are investigated. Additionally, the relations between viscous entropy...
Pore-Scale Numerical Simulation of Two-phase Flows in Periodic Porous Media Using SPH
,
Ph.D. Dissertation
Sharif University of Technology
;
Taghizadeh Manzari, Mehrdad
(Supervisor)
Abstract
Study of two-phase flowin porous media forms a basis for investigating various fluid systemsin the nature and industries. In recent years, more and more researchers use pore-scale mod-els to explore various physical phenomena occurring in complex media such as hydrocarbonreservoirs. After solving the flow equations in pore-scale, this approach can be utilized tocalculate some macroscopic values using particular forms of averaged flow field.In this research, Smoothed Particle Hydrodynamics (SPH) is used to simulate two-phaseflow in pore spaces of two- and three-dimensional porous media. The SPH method is a La-grangian meshless method that is suitable for flows with free surfaces, deformable...
Non-equilibrium Modeling of Oil Recovery by Gravity Drainage in Fractured Porous Media
, M.Sc. Thesis Sharif University of Technology ; Ghazanfari, Mohammad Hossein (Supervisor) ; Masihi, Mohsen (Supervisor)
Abstract
In this work a generalized non-equilibrium model of three-phase flow in porous media including gravity as well as capillary terms is developed and used for analysis of Riemann’s problem in several three-phase systems. The proposed model uses the extension of Barenblatt model to three-phase systems considering dynamic effects in both relative permeability and capillary pressure functions. We compare the solution of the Riemann’s problem when non-equilibrium effects are included. While equilibrium formulation develops unstable oscillatory solution in the elliptic region, non-equilibrium solution is smooth and stable. The proposed non-equilibrium model is validated by the experimental data of...