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Simulation of Non-newtonian Flow of Drilling Fluid Around the Drill String with the Olga Software
, M.Sc. Thesis Sharif University of Technology ; Jamshidi, Saeed (Supervisor)
Abstract
Because of the importance of simulations in the oil industry, there are different software applications designed for this purpose. The purpose of the simulation in the oil industry is to reduce operational errors during the operation and to achieve the most ideal mode of operation. However, in the simulation of multiphase fluid flow because of the special circumstance, simulation plays an important role in the oil industry. OLGA multiphase flow simulation software is a strong simulation software for water, oil, Gas wells, wellhead facilities, refineries and pipelines and it is capable of simulating pipelines under various dynamic conditions. Simulation of drilling hydraulic parameters is...
The Simultaneous Effect of Nano Ferric Oxide and a Liquid Additive on Viscosity and Power Transmission of Drilling Cuttings to the Surface on the Water Base Mud Drilling to Optimization of These Properties
, M.Sc. Thesis Sharif University of Technology ; Goodarznia, Iraj (Supervisor) ; Ramazani, Ahmad (Co-Advisor)
Abstract
Transportation of cuttings and efficiency of the hole cleaning has been one of the major concerns of stake holders in the oil and gas industry.This is because a successful drilling program is a key to a productive and profitable oil and gas business. A successful drilling program is as a result of an efficiently cleaned hole. On the other hand, a poor or inefficient hole cleaning implies accumulation of cuttings or formation of cuttings bed in the well. This often leads to decreased rate of penetration, increased cost of drilling, fractured formation, increased plastic viscosity of mud as a result of grinding of cuttings and stuck pipe. Hole cleaning is effected primarily with a drilling...
Modeling of Dynamic Kill in Gas-Condensate Well
,
M.Sc. Thesis
Sharif University of Technology
;
Shad, Saeed
(Supervisor)
Abstract
By exploring huge gas-condensate reservoirs, three-phase transient flow modeling demonstrates its crucial role in designing dynamic kill, relief well parameters and kill procedure of such wells. Controlling gas-condensate well needs robust transient three phase models capable of capturing discontinuities in density, geometry and velocity of phases. In this paper, two phase Advection-Upstream-Splitting-Method hybrid scheme is extended to three-phase model capable of modeling blowout and dynamic kill in gas-condensate-water wells. Density and viscosity changes are calculated using Peng-Robinson equation of state and in according, flow model parameters are corrected.The capability of this model...
Simulation of Flow Drag Reduction through Air Injection from the Porous Wall
, M.Sc. Thesis Sharif University of Technology ; Moosavi, Ali (Supervisor) ; Sadrhosseini, Hani (Supervisor)
Abstract
The effect of using backpressure of air injection in a microchannel on internal flow pressure drop were investigated in this study. Multiphase flows are commonly encountered in gas and oil industries. Flow fields in production operations are often complex and include multiphase flows of gas and liquid. Previously, because of their complex nature, these flow patterns have been mostly investigated only experimentally and empirical correlations based on the experimental data. From another point of view, it is almost impossible to experimentally realize all the flow conditions for each of the flow patterns. Nowadays computer facilities provide the tool to construct and use large-scale...
Simulation of Rapid Formation of Multicellular Spheroids in Double-emulsion Droplets with Controllable Microenvironment
, M.Sc. Thesis Sharif University of Technology ; Moosavi, Ali (Supervisor) ; Sadrhosseini, Hani (Supervisor)
Abstract
This study is aimed at simulation of double emulsion formation in a microfluidic double flow focusing device which consists of two cross-junctions connected serially. The water in oil (w/o) emulsions are produced in the first junction. In the second junction, water in oil emulsions are encapsulated by an outer aqueous phase to generate water in oil in water (w/o/w) double emulsions. Water in oil emulsions are formed in hydrophobic channels and water in oil in water double emulsions are formed in hydrophilic channels. A three phase numerical model, based on the VOF-CSF method, is developed for simulating the process of double emulsion formation. An adaptive mesh refinement technique is...
Two Dimensional Computational Modeling of Multiphase Flow in Proton Exchange Membrane Fuel Cells
, M.Sc. Thesis Sharif University of Technology ; Roshandel, Ramin (Supervisor) ; Taghizadeh Manzari, Mehrdad (Supervisor)
Abstract
Performance of Polymer Electrolyte Membrane Fuel Cells (PEMFC) at high current densities is limited to transport of reactants and products. Also at high currents, large amounts of water are gener-ated due to electrochemical reactions. Due to low temperature of PEMFC, some of the steam condenses. The amount of water existing in a PEMFC influences its performance. Shortage of water adversely af-fects cell performance by drying out the membrane. On the other hand, an excessive amount of water blocks pores of porous medium and transport of fuel becomes difficult.
In order to predict flooding and its effects on the PEMFC performance, development of a two-phase flow model is necessary. In this...
In order to predict flooding and its effects on the PEMFC performance, development of a two-phase flow model is necessary. In this...
Numerical Simulation of the Impact of a Drop with a Flat Surface in a Cross Flow, Using LBM
, M.Sc. Thesis Sharif University of Technology ; Taebi Rahni, Mohammad (Supervisor)
Abstract
In this research, numerical simulation of the impact of a drop on a flat surface with oblique velocity has been performed, using two-phase model of Lattice Boltzmann Method (conservative phase-field). During impact, it is important to investigate two-dimensional drop dynamics and to evaluate the effectiveness of the numerical method used. The model used here restores conservative phase field and preserves mass both locally and globally. In addition, to calculate the slope of the phase field, it calls the center points without engaging finite difference calculations. This makes it efficient for running parallel computations. A fixed dry and hard surface is considered and the drop impacts it...
Numerical Simulation of 2D Compressible Cavitation Flow Using Compact Finite-Difference Method
, M.Sc. Thesis Sharif University of Technology ; Hejranfar, Kazem (Supervisor)
Abstract
In the present study, the numerical simulation of 2D inviscid compressible cavitation flow is performed by using the compact finite-difference method. The problem formulation is based on the multiphase compressible Euler equations with the assumption of the homogeneous equilibrium model and the system of baseline differential equations is comprised of the continuity, momentum and energy equations for the vapor-liquid mixture. To complete the system of governing equations, the ideal gas relation is used for the vapor phase and the Tait relation is applied for the liquid phase, and therefore, the compressibility effects are considered for both the vapor and liquid phases. To analyze the flow...
Computational Two-dimensional Study of Oscillating Electrical Field on Break-up of a Drop, Using Hybrid Lattice Boltzmann-Finite Volume Method
, M.Sc. Thesis Sharif University of Technology ; Taeibi Rahni, Mohammad (Supervisor) ; Salimi, Mohammad Reza (Supervisor)
Abstract
Drop formation is an interesting field of research due to its wide-range of applications, such as drug delivery, biomedical studies, pharmaceutical industry, Lab-On-Chip (LOC) devices, etc. In recent years, researchers have used numerical studies to better understand how the process of forming and carefully examining the factors that affect quality improvement. One of the most effective methods in controlling the size and the process of drop formation is use of external force in microfluidic devices. Among the external force in this study, an electric field with oscillating current was used. Rapid methods for creating, deforming, and breaking up of drops in microfluidic applications are...
Numerical and Experimental Study of a Thermal Energy Storage System Based on Accelerating the Melting of a Phase Change Material by Using an Auxiliary Fluid
, M.Sc. Thesis Sharif University of Technology ; Darbandi, Masoud (Supervisor) ; Shafii, Mohammad Behshad (Supervisor)
Abstract
The study of heat transfer using solid-liquid phase shifting has attracted much attention in applied engineering fields such as latent heat energy storage, building walls, waste energy recovery, battery thermal management, and more. Over the past few decades, the literature on phase shift has grown tremendously in terms of theory, laboratory, and numerical studies. Melting of phase change materials in rectangular chambers due to its wide range of engineering applications in fields such as casting, metallurgy, heat energy storage, and heat exchangers used in buildings, as well as aerospace issues including the use of These systems have been the subject of numerous studies on space missions to...
LBM Computational Simulation of Oscillations Caused by Formation and Detachment of Drops
, M.Sc. Thesis Sharif University of Technology ; Taeibi Rahni, Mohammad (Supervisor) ; Ebrahimi, Abbas (Supervisor)
Abstract
Formation and detachment of drops are of fundamental importance in studying two-phase flows, such as ink jet printing, emulsion, and spray. Drops are formed under the effects of surface tension forces. After formation, forces like gravity detach the drop from the rest of the fluid. The flow rate is varied from dripping to jetting regime. In this project, formation and detachment of drops were simulated, using LBM with phase field model, which can simulate flows with high-density ratios and is a robust method for applying wetting condition on the walls. Results were validated using single-phase and two-phase flows. After code validation, the oscillations caused by formation and detachment of...
Implementing Appropriate Numerical Filters in the Lattice Boltzmann Method for Solving Multiphase Incompressible Flows with Large Density Ratio
, M.Sc. Thesis Sharif University of Technology ; Hejranfar, Kazem (Supervisor)
Abstract
In this study, two finite-difference lattice Boltzmann methods (FDLBM) are applied and assessed for the simulation of two-phase liquid-vapor flows with high density ratios. For this aim, the He-Shan-Doolen type lattice Boltzmann multiphase model is used and the spatial derivatives in the resulting system of equations are discretized by using the second-order central difference and modified Lax-Wendroff schemes. Suitable numerical dissipation terms and filters are applied to regularize the numerical solution and remove spurious waves generated by flow nonlinearities in smooth regions and at the same time to remove the numerical oscillations in the interface region of the two phases.Three...
Numerical Simulation of A Vortex Cooled Combustion Chamber
,
M.Sc. Thesis
Sharif University of Technology
;
Farshchi, Mohammad
(Supervisor)
Abstract
The aim of the present research is to investigate the combustion chamber cooling with vortex method in presence of kerosene and liquid oxygen as propellants. For this purpose, a part of oxidizer is entered into the cylindrical combustion chamber tangentially (from bottem of the chamber), and creates a vortex flow (outer vortex). With motion of created outer vortex along the wall and eventually hit its top wall (the head of the chamber), secondary vortex (inner vortex) occurs along the center line, with a downward direction (opposite to the primary vortex). The fuel and other part of the oxidizer injection is also carried in the head of chamber, so by mixing the fuel and oxidizer that happens...
Modeling and Simulation of Vacuum Assisted Resin Transfer Molding Process with Flexible Tooling
, M.Sc. Thesis Sharif University of Technology ; Abedian, Ali (Supervisor)
Abstract
Resin Transfer Molding (RTM) which is one of the categories of Liquid Composite Molding (LCM) process, is considered as one of the most important process in polymer composite manufacturing. To improve this manufacturing method and reaching higher qualities, numerous modified methods has been developed. One of these modified methods is Vaccum Assisted Resin Trasnfer Molding with Flexible Tooling which is considerably applicable in manufacturing parts with high quality, large and complex geometry. Although, this manufacturing method has variety of advantages, there are some problems such as void formation making production difficult and dependent to experimental trial and error. So numerical...
Numerical Modeling of Liquid Jet Breakup Using SPH Method
, M.Sc. Thesis Sharif University of Technology ; Morad , Mohammad Reza (Supervisor) ; Omidvar, Pourya (Supervisor)
Abstract
Smoothed Particle Hydrodynamics (SPH) is a numerical Lagrangian meshless method which has numerous applications in astrophysics, hydrodynamics, free-surface flows, jets and sprays formation. Atomization of continuum liquid to fine droplets or in other words, liquid breakup processes are emerged in many engineering applications such as fuel sprays inside the combustion chamber of internal combustion engines that sizes of produced sprays significantly influence the engine’s efficiency. This research is accomplished to investigate the one-phase and two-phase flows of liquid jet breakup. For this aim, an open source code called SPHysics which solves the flow field by SPH method is utilized. This...
Numerical Simulation of Cavitating Flows with Compressibility Effects
, M.Sc. Thesis Sharif University of Technology ; Hejranfar, Kazem (Supervisor)
Abstract
In this study, the numerical simulation of cavitating flows with compressibility effects is performed. The algorithm employs the multiphase Euler equations with homogeneous equilibrium model. The baseline differential equations system is similar to the one-phase system of equations and comprised of the mixture density, mixture momentums and mixture energy equations. Thephases considered for cavitating flows is liquid-vapor and liquid-gas fields. The system of governing equations is discretized using a cell-centered finite volume AUSM’s upwind scheme. The computations are presented for steady noncavitating/cavitating flows around 1D/2Dproblems for different conditions. A sensitivity study is...
Investigation the Distribution Pattern and Life-Time Duration of Dense Non-Aqueous Phase Liquids (DNAPL) in Heterogeneous Porous Media (Fractured Media)
, M.Sc. Thesis Sharif University of Technology ; Ataie Ashtiani, Behzad (Supervisor)
Abstract
Dense non-aqueous phase liquid accounts for a large share of groundwater pollution. In oil-rich countries, including Iran, the emission of this type of pollutant is mainly through leakage from concrete and steel tanks belonging to refineries and gas stations. The dissolution of these pollutants in groundwater and the vapor intrusion into residential homes increased the importance of developing efficient treatment methods. To choose the best method, it is necessary to gain sufficient knowledge of how these types of contaminants are distributed in the subsurface and how contaminants change and move over time. Heterogeneity, especially in the form of fracture, is one of the challenges to...
Development of a Multi-functional Soil Column for Studying Bioremediation and Multiphase Flow
, M.Sc. Thesis Sharif University of Technology ; Sadeghi, Hamed (Supervisor)
Abstract
Soil and water pollution is one of the most common types of pollution in terrestrial and aquatic ecosystems. The development of mines and the oil and petrochemical industry on one hand and the non-compliance with environmental requirements on the other hand have caused large amounts of hydrocarbon pollutants and heavy metals to enter the environment in recent decades. Petroleum materials and heavy metals leak into the surrounding environment during drilling and extraction in oil sites and mines or during land and sea transportation, despite the measures taken to control their pollution. The conducted studies show that human industrial activities are the only cause of environmental pollution...
Multiscale Modelling of Non-Isothermal Multiphase Flow in Heterogeneous Porous Media with Computational Homogenization Approach
, Ph.D. Dissertation Sharif University of Technology ; Khoei, Amir Reza (Supervisor)
Abstract
In the real engineering problems, the existing materials in the nature or human-made materials, contain different heterogeneities from the view of small scale. Reinforced composite materials and porous media containing grains or micro-cracks are some examples of these materials. Due to the large amount of these heterogeneities as well as the small size, direct modelling of these micro-structures requires extremely high computational and memorial cost. Also, the equivalent models introduced in the literature, have strong limitations and therefore, cannot capture accurate behavior of the material. Hence, multiscale methods have been proposed in order to model these heterogeneous media with...
Dynamic Modeling of Cohesive Crack Propagation in Multiphase Porous Media Using the Extended Finite Element Method
, Ph.D. Dissertation Sharif University of Technology ; Khoei, Amir Reza (Supervisor)
Abstract
In this thesis, a fully coupled numerical model is developed for the modeling of the cohesive crack propagation and hydraulic fracturing in porous media using the extended finite element method in conjunction with the cohesive crack model. The governing equations, which account for the coupling between various physical phenomena, are derived within the framework of the generalized Biot theory. The solid phase displacement, the wetting phase pressure and the capillary pressure are taken as the primary variables of the three-phase formulation. The other variables are incorporated into the model via the experimentally determined functions that specify the relationship between the hydraulic...