Numerical Study of Sand Production in Oil Extracting Wells

, M.Sc. Thesis Sharif University of Technology Abbasi, Babak (Author) ; Pak, Ali (Supervisor)

Abstract

Sand production in petroleum industry is a phenomenon of solid particles being produced together with reservoir fluid. This phenomenon is costing industry billions of dollars every year. Corrosion of the pipelines and other instruments, sand-oil separation cost, possible wellbore choke and repeated shut-in and clean-up of the wellbore are some of examples of the costs. On the other hand, a controlled sanding or even sand production invocation has proved to be very effective in increasing production rate, especially in heavy oil recovery, asphalt wells and low PI wells. Discovering the best sand controlling procedure in oil extracting wells, parameters that have the most important effects on...

Design and Simulation of ELoran Receiver

, M.Sc. Thesis Sharif University of Technology Abbasi, Fatemeh (Author) ; Fotowat Ahmadi, Ali (Supervisor)

Abstract

In recent years, eLoran system has been introduced as backup to global navigation systems like GPS, because of their vulnerability. eLoran is a low frequency (100 kHz) system. Its long wavelength allows indoor positioning.
Main eLoran advantages rather than Loran-C are: better accuracy (near 10m), using 9th pulse positioning modulation (PPM) as loran data channel (LDC) and all-in-view receivers
In this thesis, eLoran pulses are simulated in GRI. Also, a new analoge-digital circuit for faster pulse detection is developed.
Also, it is proved that an oscillator with same frequency and phase as enterance signal, responses faster than a band pass filter and envelope detector. So, a...

Modeling of Yield Behavior of Rubber Modified Epoxies

, M.Sc. Thesis Sharif University of Technology Abbasi, Mohammad (Author) ; Kuchakzadeh, Mohammad Ali (Supervisor)

Abstract

Because of increasing usage of modified polymers and consequent necessity for investigation and modeling of mechanical behavior of these materials, it is important to get a yield criterion for these materials. For this purpose the Gurson yield criterion presented for porous metals, was modified with regard to mechanical properties of polymers. Indeed pressure sensitivity of polymers and their large elastic strain during deformation, makes using of Gurson yield criterion problematic for modified polymers.
For modification of Gurson criterion, macroscopic hydrostatic yield stress equation was derived for a thick-walled spherical shell of epoxy and then Gurson criterion was modified with...

Design and Impacts of Virtual Reality Games on Social and Cognitive Skills of Children with Autism Spectrum Disorder

, M.Sc. Thesis Sharif University of Technology Abbasi, Sajjad (Author) ; Taheri, Alireza (Supervisor) ; Meghdari, Ali (Supervisor)

Abstract

Autism is a neurodevelopmental disorder for which there is no definitive cure and it is increasing every year for people with this disorder. In the last decade, the use of virtual environment to improve the skills of people on the autism spectrum has increased. In this research, a semi-intelligent algorithm was designed for a virtual reality game that could provide a more appropriate step to the user according to the user's responses. Our focus is on designing games to strengthen the child in terms of shared attention and eye contact. In other words, we seek to create a virtual environment with the ability to intelligently adapt to interact with our user and turn it into a suitable coaching...

Energy Loss of a Heavy Quark Moving Through Quark-Gluon Plasma

, Ph.D. Dissertation Sharif University of Technology Abbasi, Navid (Author) ; Arfaei, Hessamaddin (Supervisor) ; Davody, Ali (Co-Advisor)

Abstract

One of the approaches to study the plasma phase of quantum chromodynamics is to investigate the motion of probes in the quark-gluon plasma. In the case of a moving heavy quark, the medium affects the quark by exerting a drag force on it. Since we finally detect hadron jets in detectors, the goal is to compute the darg force formula in a form compatible with the espectrum of final hadrons. On the other hand due to strong coupling, perturbative methods fail in the medium. So a nonperturbative method is needed. We use gauge gravity duality and compute the drag force exerted on a heavy quark in the hydrodynamic regime, up to first order in derivative expansion

Effects of Static Restoration Phenomena on Microstructure and Mechanical Properties of A286 Superalloy

, M.Sc. Thesis Sharif University of Technology Sahrapour, Peyman (Author) ; Karimi Taheri, Ali (Supervisor) ; Abbasi, Mahdi (Supervisor)

Abstract

In this investigation, effects of static restoration phenomena on microstructure and mechanical properties of A286 superalloy were studied. Therefore, single hit and double hit hot compression and hot rolling with different delay time at temperatures of 1050 and 1100 °C in strain rate of 0.1 and 6 s-1 were applied. In addition, annealing of cold compressed and cold rolled samples with various amounts of strains in temperature range of 1000-1100 °C were performed. Finally the best method for forming of A286 superalloy was proposed.Single hit hot compression test results shows that dynamic recovery and dynamic recrystallization occurred at temperatures of 1050 and 1100 °C respectively....

An Investigation into the Kinetics of Dynamic Recrystallization of Fe-Ni Alloy

, M.Sc. Thesis Sharif University of Technology Dehghan, Hossein (Author) ; Karimi Taheri , Ali (Supervisor) ; Abbasi, Mehdi (Supervisor)

Abstract

The A-286 superalloy is an iron-nickel base alloy having properties such as oxidation resistance and high mechanical strength. In addition, good producibility and high workability are the important properties of this alloy. In the present work dynamic restoration mechanism of A-286 supper alloy during thermo-mechanical processing has been studied. The aim is to verify the dominant restoration mechanism in different deformation conditions and also to determine the desire deformation parameters for hot rolling. In this regard, utilizing compression test in the range of 950 to 1100ºC and strain rate of 0.001 to 1 per second, the strain-stress curve for this alloy was obtained. After correction...

Investigation of Effect of Hot rolling Parameters on Mechanical and Physical Properties of a Fe-Ni-Co Alloy

, M.Sc. Thesis Sharif University of Technology Yazdani, Mohammad (Author) ; Karimi Taheri, Ali (Supervisor) ; abbasi, mehdi (Supervisor)

Abstract

Fe-29Ni-17Co alloy with commercial name “Kovar” is an alloy with low expansion coefficient. The main specification of this alloy is to maintain this property at the high temperatures that is used in sealing of glass-metal. Achieving to desirable physical properties associated with suitable mechanical properties is the purpose of related industries. However the effect of cold work and heat treatment was studied on the physical properties of this alloy, there is no report about the effect of the hot work. Thus, in this investigation, the effect of the hot work on the physical and mechanical properties of Kovar was studied. At first, slabs of Kovar alloy were cast and remelted. Then,...

TheEffect of Hot Rolling Variables on the Shape Memory Properties of Ni-Ti Shape Memory Alloys

, M.Sc. Thesis Sharif University of Technology Ahadi, Aslan (Author) ; Karimi Taheri, Ali (Supervisor) ; Abbasi, Mahdi (Supervisor)

Abstract

In the present study the hot deformation behavior and the effect of hor rolling variables on the shape memory properties of a Ni-Ti shape memory alloy was studied. In order to simulate the hot compression test Abaqus softeware was employd. The results proved the pronounced increase in the specimen temperature at high strain rates and low temperatures (47 °C at strain rate of 1 s-1 and temperature of 700 °C). Thus, the effect temperature rise due to deformation heating on the characterisitics of the flow curves was eliminated. Afterwards, the corrected constitutive equation of the alloy was obtained and the rolling plan was designed. Shape memory measurments showed that two-way shape memory...

Modeling of Biological Cells with Applications to the Design of a Nano-Micro Gripper Used in Cell Manipulation

, M.Sc. Thesis Sharif University of Technology Abbasi, Ali Asghar (Author) ; Ahmadian, Mohammad Taghi (Supervisor) ; Vossoughi, Golamreza (Supervisor)

Abstract

Grasping and manipulation of biological cells have an extensive applications in genetics ,cell proliferation ,cell injection and etc. In robotic manipulation ,it is often assumed that the objects being handled are rigid and only small deformations occurred during manipulation. this does not apply for the case of biological cells. biological cells are highly deformable structures, and their material properties are not well quantified. Therefore strategies for characterizing and manipulating of such deformable objects needs to develop. Different experimental techniques have recently been used and devised to study biological cells. On the one hand, although this experimental techniques have...

Modeling the Solar Heat Pump with an Energy Storage System

, M.Sc. Thesis Sharif University of Technology Abbasi Godarzi, Ali (Author) ; Samimi , Jalal (Supervisor) ; Vesaghi, Mohammad Ali (Supervisor)

Abstract

Purpose of ongoing thesis is providing a tool for suitable modeling, increase efficiency and decrease construction cost of solar absorption heat pump. At first, the solar absorption heat pump is modeled by the thermodynamic laws. Then, this model is converted to the new standard mathematical programming model using exergy and thermodynamic Analysis with considering all technical and economic constrains. This mathematical model is optimized by Genetic algorithm (GA). Because of the nonlinear objective function and the constraint, GA is used as optimization algorithm. After applying GA, optimized parameters of cycle heat exchanger designing and its electricity consumption are calculated....

Numerical investigation of effects of uniform magnetic field on heat transfer around a sphere

, Article International Journal of Heat and Mass Transfer ; Volume 114 , 2017 , Pages 703-714 ; 00179310 (ISSN) Abbasi, Z ; Molaei Dehkordi, A ; Abbasi, F ; Sharif University of Technology

Elsevier Ltd 2017

Abstract

In this article, ferrohydrodynamic forced-convection heat transfer from a heated sphere embedded in a ferrofluid in the presence of the uniform external magnetic field has been studied numerically for the first time over a wide range of Reynolds number value, nanoparticle diameter, particle volume fraction, and magnetic field intensity. Despite the uniform external magnetic field applied, the internal magnetic field near the sphere could be nonuniform due to the considerable difference between the relative magnetic permeability of the sphere and the surrounding medium. Kelvin body force arises from this nonuniformity and induces vortexes near the sphere. These vortexes disturb the boundary...

A method for simulation of vapour cloud explosions based on computational fluid dynamics (CFD)

, Article Journal of Loss Prevention in the Process Industries ; Volume 24, Issue 5 , 2011 , Pages 638-647 ; 09504230 (ISSN) Tauseef, S. M ; Rashtchian, D ; Abbasi, T ; Abbasi, S.A ; Sharif University of Technology

2011

Abstract

The effectiveness of the application of CFD to vapour cloud explosion (VCE) modelling depends on the accuracy with which geometrical details of the obstacles likely to be encountered by the vapour cloud are represented and the correctness with which turbulence is predicted. This is because the severity of a VCE strongly depends on the types of obstacles encountered by the cloud undergoing combustion; the turbulence generated by the obstacles influences flame speed and feeds the process of explosion through enhanced mixing of fuel and oxidant. In this paper a CFD-based method is proposed on the basis of the author's finding that among the various models available for assessing turbulence, the...

Thin film graphene oxide membrane: challenges and gas separation potential

, Article Korean Journal of Chemical Engineering ; Volume 35, Issue 5 , May , 2018 , Pages 1174-1184 ; 02561115 (ISSN) Abbasi, F ; Karimi Sabet, J ; Ghotbi, C ; Abbasi, Z ; Sharif University of Technology

Springer New York LLC 2018

Abstract

Graphene oxide membranes were prepared by vacuum and pressurized ultrafiltration methods on the 12% modified Polyacrylonitrile (12mPAN) substrate to specify challenges, salient features, future directions, and potential of GO membrane for separation fields using characterization techniques and gas separation test (studied gases are CO2, He and N2), which is an efficient tool for better understanding of GO membrane behavior. GO membrane structure was examined over a wide range of parameters, such as pore size range of substrate and its surface properties, pH of GO dispersion, GO content, synthesis pressure, operating pressure and temperature. The results show that the GO content does not hold...

Conversion of CO into CO2 by high active and stable PdNi nanoparticles supported on a metal-organic framework

, Article Frontiers of Chemical Science and Engineering ; 2021 ; 20950179 (ISSN) Abbasi, F ; Karimi Sabet, J ; Abbasi, Z ; Ghotbi, C ; Sharif University of Technology

Higher Education Press Limited Company 2021

Abstract

The solubility of Pd(NO3)2 in water is moderate whereas it is completely soluble in diluted HNO3 solution. Pd/MIL-101(Cr) and Pd/MIL-101-NH2(Cr) were synthesized by aqueous solution of Pd(NO3)2 and Pd(NO3)2 solution in dilute HNO3 and used for CO oxidation reaction. The catalysts synthesized with Pd(NO3)2 solution in dilute HNO3 showed lower activity. The aqueous solution of Pd(NO3)2 was used for synthesis of mono-metal Ni, Pd and bimetallic PdNi nanoparticles with various molar ratios supported on MOF. Pd70Ni30/MIL-101(Cr) catalyst showed higher activity than monometallic counterparts and Pd + Ni physical mixture due to the strong synergistic effect of PdNi nanoparticles, high distribution...

Conversion of CO into CO2 by high active and stable PdNi nanoparticles supported on a metal-organic framework

, Article Frontiers of Chemical Science and Engineering ; 2021 ; 20950179 (ISSN) Abbasi, F ; Karimi Sabet, J ; Abbasi, Z ; Ghotbi, C ; Sharif University of Technology

Higher Education Press Limited Company 2021

Abstract

The solubility of Pd(NO3)2 in water is moderate whereas it is completely soluble in diluted HNO3 solution. Pd/MIL-101(Cr) and Pd/MIL-101-NH2(Cr) were synthesized by aqueous solution of Pd(NO3)2 and Pd(NO3)2 solution in dilute HNO3 and used for CO oxidation reaction. The catalysts synthesized with Pd(NO3)2 solution in dilute HNO3 showed lower activity. The aqueous solution of Pd(NO3)2 was used for synthesis of mono-metal Ni, Pd and bimetallic PdNi nanoparticles with various molar ratios supported on MOF. Pd70Ni30/MIL-101(Cr) catalyst showed higher activity than monometallic counterparts and Pd + Ni physical mixture due to the strong synergistic effect of PdNi nanoparticles, high distribution...

Conversion of CO into CO2 by high active and stable PdNi nanoparticles supported on a metal-organic framework

, Article Frontiers of Chemical Science and Engineering ; Volume 16, Issue 7 , 2022 , Pages 1139-1148 ; 20950179 (ISSN) Abbasi, F ; Karimi Sabet, J ; Abbasi, Z ; Ghotbi, C ; Sharif University of Technology

Higher Education Press Limited Company 2022

Abstract

The solubility of Pd(NO3)2 in water is moderate whereas it is completely soluble in diluted HNO3 solution. Pd/MIL-101(Cr) and Pd/MIL-101-NH2(Cr) were synthesized by aqueous solution of Pd(NO3)2 and Pd(NO3)2 solution in dilute HNO3 and used for CO oxidation reaction. The catalysts synthesized with Pd(NO3)2 solution in dilute HNO3 showed lower activity. The aqueous solution of Pd(NO3)2 was used for synthesis of mono-metal Ni, Pd and bimetallic PdNi nanoparticles with various molar ratios supported on MOF. Pd70Ni30/MIL-101(Cr) catalyst showed higher activity than monometallic counterparts and Pd + Ni physical mixture due to the strong synergistic effect of PdNi nanoparticles, high distribution...

Improved method for increasing accessible pores of MIL-101(Cr) by encapsulation and removal of Phosphotungstic acid (PTA): Pd/PTA-MIL-101(Cr) as an effective catalyst for CO oxidation

, Article Journal of Cleaner Production ; Volume 347 , 2022 ; 09596526 (ISSN) Abbasi, F ; Karimi Sabet, J ; Abbasi, Z ; Ghotbi, C ; Sharif University of Technology

Elsevier Ltd 2022

Abstract

This study forwards a novel and simple approach for encapsulation of Phosphotungstic acid (PTA) into MIL-101(Cr) cavities to develop PTA-MIL-101(Cr) with a high surface area. In this method, the resulting surface area of PTA-MIL-101(Cr) (3563 m2/g) is 1.72 times that of MIL-101(Cr) due to the existence of more accessible pores which are formed by leaching of PTAs incorporated inside MIL-101(Cr) pores during the intense washing. Catalysts are investigated in CO oxidation under atmospheric pressure and feed composition of 1%CO, 20%O2, and 79%He. 3%Pd/PTA-MIL-101(Cr) shows 100%CO conversion at T = 145 °C and outperforms PTA, PTA-MIL-101(Cr), Pd/PTA, 1–3%Pd/MIL-101(Cr), Pd-PTA/MIL-101(Cr), and...

Investigation into the effects of weld zone and geometric discontinuity on the formability reduction of tailor welded blanks

, Article Computational Materials Science ; Volume 59 , 2012 , Pages 158-164 ; 09270256 (ISSN) Abbasi, M ; Ketabchi, M ; Ramazani, A ; Abbasi, M ; Prahl, U ; Sharif University of Technology

2012

Abstract

Numerous advantages of application of tailor welded blanks (TWBs) in automobile industry, namely reduction of weight, fuel consumption and air pollution, have made the manufacturers eager to investigate in this field. On the other hand, while experiments generally provide valuable information in regard with mechanical behaviors, but utilization of simulation methods has extended vastly due to time and cost saving issues. One challenging issue in numerically analyzing the forming behavior of transversely welded TWBs, welded by laser welding methods, has been the presence of weld zone. While some researchers believe that during simulation, the weld zone can be neglected due to its minority and...

A neural network applied to estimate process capability of non-normal processes

, Article Expert Systems with Applications ; Volume 36, Issue 2 PART 2 , 2009 , Pages 3093-3100 ; 09574174 (ISSN) Abbasi, B ; Sharif University of Technology

2009

Abstract

It is always crucial to estimate process capability index (PCI) when the quality characteristic does not follow normal distribution, however skewed distributions come about in many processes. The classical method to estimate process capability is not applicable for non-normal processes. In the existing methods for non-normal processes, probability density function (pdf) of the process or an estimate of it is required. Estimating pdf of the process is a hard work and resulted PCI by estimated pdf may be far from real value of it. In this paper an artificial neural network is proposed to estimate PCI for right skewed distributions without appeal to pdf of the process. The proposed neural...