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taghikhani--saeed
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A Model for Effects of Hole Cleaning on Pipe Sticking by Considering Well, Fluid and Cutting Concentration Condition
, M.Sc. Thesis Sharif University of Technology ; Taghikhani, Vahid (Supervisor) ; Jamshidi, Saeed (Co-Supervisor)
Abstract
Poor hole cleaning while drilling due to problems such as pipe sticking and ROP reducing will increase drilling cost. It is almost impossible to optimize the hole cleaning during the well planning due to the large number of effective parameters, so it is very important to monitor the hole cleaning conditions while drilling. The best way to monitor the well condition during drilling is using the real time drilling data (RTDD). Hook load (HKL) is one of many RTDD parameters that measured at the surface during drilling operations so it can be used to evaluate the hole cleaning condition. In this research, how to process the raw data recorded while drilling has been investigated. In the next...
Production Well Multi-Phase Flow Measurement Using Ultrasonic Technology
, M.Sc. Thesis Sharif University of Technology ; Taghikhani, Vahid (Supervisor) ; Sahd, Saeed (Supervisor) ; Amjadi, Ahmad (Co-Supervisor)
Abstract
Flow measurement in both types of single phase and multiphase has a crucial place in a wide variety of industries, specially petroleum industry. for single phase flowmeters, improving their precision using different types of mechanical, mathematical and analytical techniques will be considered as an important step. Using multiphase flow meters will cause no need of volume catching and costly separators and also make us capable of taking well-timed decisions in production management. for making flow meters weather multiphase or single phase, there is a crucial need of a multiphase flow loop. To achieve that, an 8-meter-long flow loop using transparent Plexiglas pipes with inside diameter of...
Prediction of Hydraulic Fracturing Technology in Naturally Fractured Rocks, by Considering Immiscible Two-phase Flow
, Ph.D. Dissertation Sharif University of Technology ; Taghikhani, Vahid (Supervisor) ; Ayatollahi, Shahab (Supervisor) ; Shad, Saeed (Supervisor) ; Ranjbaran, Abdolrasul ($item.subfieldsMap.e)
Abstract
To have a deeper understanding of Hydraulic fracturing operation, in this study four important parts in this field was developed and simulated. In the first part, continuity and momentum equations for a single phase flow in a propagating penny-shaped fracture inside an impermeable matrix was revisited based on a fixed coordinate system. Its correctness was validated against experimental data and its features were compared with the well-known lubrication theory in analytical form. The new derived continuity equation caused the fracture tip to have a positive and finite pressure while, the conventional model predicted negative infinity for that. In the second part, Finite Volume method was...
Performance of three-level spectrally encoded spreadtime CDMA in the presence of multiple interferences [electronic resource]
, Article IET Communications ; July 2011, Volume 5, Issue 10, P. 1328-1335 ; Mashhadi, Saeed ; Salehi, J. A ; Sharif University of Technology
Abstract
In this study the authors present an in-depth study, analysis and discussion on maximum likelihood (ML)-based receiver for a typical spectrally encoded spread-time CDMA in the presence of multiple narrowband interference (NBI) signals in an additive white Gaussian noise channel. Furthermore, the authors demonstrate that by combining useful properties of ML-based receiver and three-level codes, that is, codes with values of -1, 0, +1, the authors can introduce a new strategy in which superior performance with respect to previous receiver structure based on two-level codes, that is, codes with values of -1, +1, can be attained. With the help of an example, the authors drive, first, the...
Simulation of High Frequency Acoustic Waves in Porous Media
, M.Sc. Thesis Sharif University of Technology ; Farshchi, Moammad (Supervisor)
Abstract
In this study, a numerical investigation of propagation of sound through a fluid-saturated porous column has been proposed so that we can analyze the effects of porous media parameters on decreasing sound amplitude. The mathematical model applied for our simulation is based on Biot equations solved by an explicit finite difference method. Since Biot model is exclusively applicable to porous solids saturated with single fluid phase, in order to simulate a porous solid saturated with two immiscible fluids, we exploited the general Eulerian model instead of Biot model. Efficiency of porous sound absorbers is directly influenced by four major parameters which are porosity, rigidity and thickness...
Evaluating the Effect of Crumb Rubber as a Binder Modifier on Bonding Properties of Chip Seal Against Environmental Effect
, M.Sc. Thesis Sharif University of Technology ; Motamed, Arash (Supervisor)
Abstract
Crumb Rubber is one of the main polymer modifiers of binders. This modifier can improve chip seal performance against ravelling (aggregate loss). The most concerning distress in chip seal is ravelling. Aggregate loss is not restricted to the early life of chip seal, but continues throughout the service life. Chip seal can be made with hot binders or emulsion binders. These two type of binder were modified with 7% and 15% of crumb rubber in applicable way. Then, two major environmental effect on chip seal performance, freeze-thaw and asphalt aging, were investigeted based on laboratory test. For this purpose, authors used chip seal bonding test. Chip seal bonding test is developed recently...
Experimental Analysis and Modeling of Crude Oil Viscosity at Downhole Conditions Using the Frtiction Theory
, M.Sc. Thesis Sharif University of Technology ; Taghikhani, Vahid (Supervisor)
Abstract
Viscosity is one of the most important properties used in simulating and optimizing transportation design and hydrocarbon reservoirs simulation. In this work, a new model based on the friction theory was used to correlate the viscosity for six different live and dead oil samples taken from the south of the Iranian oil region. As expounded by other researchers, in the friction theory, an equation of state is used to express the intermolecular viscous interactions. In model presented in this work, the standard cubic equations of state such as the SRK and PR were used to correlate the viscosity data for the samples under investigation. In the new model, the effect of critical viscosity on the...
Theoretical investigation of the hydrogen abstraction reaction of the OH radical with CH2FCH2F (HFC-152): A dual-level direct dynamics study
, Article Journal of Physical Chemistry A ; Volume 111, Issue 33 , 2007 , Pages 8095-8103 ; 10895639 (ISSN) ; Parsafar, G. A ; Sharif University of Technology
2007
Abstract
The hydrogen abstraction reaction of the OH radical with CH 2FCH22F (HFC-152) is studied theoretically over the 150-3000 K temperature range. In this study, the two most recently developed hybrid density functional theories, namely, BBlK and MPWBlK, are applied, and their efficiency in reaction dynamics calculation is discussed. The BBlK/6-31+G(d,p) method gives the best result for the potential energy surface (PES) calculations, including barrier heights, reaction path information (the first and second derivatives of PES), geometry of transition state structures, and even weak hydrogen bond orientations. The rate constants were obtained by the dual-level direct dynamics with the...
Landslide Hazard Zonation of Mazandaran Province With Emphasis on Micro-Zonation of Powerhouses in Mazandaran Province Against Landslide Hazard
, M.Sc. Thesis Sharif University of Technology ; Haeri, Mohsen (Supervisor)
Abstract
Landslides, like earthquakes, floods, and volcanoes, are important natural disasters that occur frequently in the mountainous and high regions of our country, especially in the Alborz and Zagros regions, which induce considerable damages. Various factors such as topography, lithology, weather conditions, hydrology, tectonics, earthquakes, and various human activities are effective factors in the instability of natural and man-made slopes. Not one factor can cause instability in slops, however, a combination of the named factors may cause landslides. Therefore, knowing the factors affecting the occurrence of landslides and identifying different areas in terms of sensitivity to their...
Simulation of Scale Formation at Gas Reservoir Conditions with and without Hydrate Inhibitors
, M.Sc. Thesis Sharif University of Technology ; Taghikhani, Vahid (Supervisor)
Abstract
Since the beginning of oil, gas and gas condensate production, the prediction of the formation of mineral scales in different operating conditions has been a serious challenge. Mineral scale are solid particles that are separated from the free water in the reservoir due to changes in the production conditions in terms of temperature and pressure or the fluid composition of the production fluid of reservoir, and there is a possibility of their deposing on the wall of the well column and in the production system, where The way of production from reservoirs faces serious risks. free water, which is permanently entering the pipeline, contains all kinds of salts in the structure of the fluid...
Investigation of Multiphase Flow in Oil Wells (with Focus on Two Phase Flow), Flow Pattern Recognition and Modeling
, M.Sc. Thesis Sharif University of Technology ; Shad, Saeed (Supervisor) ; Jamshidi, Saeed (Supervisor)
Abstract
The concurrent flow of oil and water is a common occurrence in the field of multiphase flow in different fields including petroleum industry. In oil and gas, production engineers often face a situation in which more than one phase is flowing through the producers. In such conditions an accurate assessment of pressure loss inside the well plays a vital role in efficient and effective production planning. Changes in well orientation, wellbore diameter, reservoir and fluid properties as well as fluid flow rates are among parameters in which will affect the flow patterns that can occur inside a well during its life time. These flow patterns are created as a result of a competition between...
Casing Design Optimization Considering Drilling and Production Conditions
, M.Sc. Thesis Sharif University of Technology ; Jamshidi, Saeed (Supervisor) ; Shad, Saeed (Supervisor)
Abstract
Casing design is one of the most expensive parts in the drilling of oil wells, and any cost reduction with the basic design of these casing strings will significantly reduce the total cost of the operation. In recent years, occurring scenarios-based casing design has become popular; Because in many cases, it eliminates non-occurring scenarios such as gas kick and saves on drilling costs. In this study, we have tried to investigate all scenarios that may occur during the lifetime of the well, whether drilling or production, and for each well, based on its own field information, possible scenarios for each casing part are selected separately and the applying loads are calculated. For this...
Partitioning of penicillin G acylase in aqueous two-phase systems of poly(ethylene glycol) 20000 or 35000 and potassium dihydrogen phosphate or sodium citrate
, Article Journal of Chemical and Engineering Data ; Volume 55, Issue 1 , 2010 , Pages 243-248 ; 00219568 (ISSN) ; Vossoughi, M ; Taghikhani, V ; Sharif University of Technology
2010
Abstract
The partitioning of penicillin G acylase in aqueous two-phase systems (ATPS's) containing poly(ethylene glycol) (PEG) 20000 or 35000 and potassium dihydrogen phosphate (KH2PO4) or sodium citrate (C 6H5Na3O7 ·5H2O) has been measured at three temperatures, (301.2, 307.2, and 310.2) K. The effects of temperature, polymer molecular weight, and polymer and salt concentrations on the partitioning of penicillin G in the ATPS were studied. The experimental data showed that the composition of salt has a large effect on partitioning of penicillin G in ATPS, and the temperature of the system has a small effect on the partitioning. The UNIFAC-FV group contribution model (Pazuki et al., Ind. Eng. Chem....
A new multiphase and dynamic asphaltene deposition tool (MAD-ADEPT) to predict the deposition of asphaltene particles on tubing wall
, Article Journal of Petroleum Science and Engineering ; Volume 195 , 2020 ; Jamshidi, S ; Taghikhani, V ; Sharif University of Technology
Elsevier B.V
2020
Abstract
As expounded, the precipitation and deposition of asphaltene particles in pipelines has been proved to be the most challenging flow assurance problem due to its unknown and complex behaviors. In this work, a new multicomponent, multiphase and dynamic tool was developed to model the aggregation and deposition of asphaltene particles in a bulk medium. The multiphase and dynamic asphaltene deposition tool, shortened as MAD-ADEPT is, in fact, a modified version of the previously developed ADEPT. The new tool was developed to make the asphaltene deposition and aggregation concepts in oil production wells more predictable. To tackle the complexity of the asphaltene problem, a bespoke algorithm was...
Application of the Pitzer and the MSA-based models in predicting the activity and the osmotic coefficients of aqueous electrolyte solutions
, Article Scientia Iranica ; Volume 12, Issue 3 , 2005 , Pages 280-289 ; 10263098 (ISSN) ; Ghotbi, C ; Taghikhani, V ; Sharif University of Technology
Sharif University of Technology
2005
Abstract
The GV-MSA, the BMCSL-MSA and the Pitzer models were used to correlate the individual, the mean ionic activity coefficients and the osmotic coefficients of symmetric and asymmetric electrolyte solutions. In order to compare the results obtained from the GV-MSA with those obtained from the Pitzer and the BMCSL-MSA models, the same experimental data and the same minimization procedure were used and the new sets of parameters for the BMCSL-MSA and the Pitzer models were also reported. The values for the osmotic coefficients of electrolyte solutions were calculated directly using the values of the mean ionic activity coefficients obtained from the models studied in this work. The results for the...
Investigation of diffusion and deposition of TiO2 nanoparticles in sandstone rocks for EOR application
, Article 76th European Association of Geoscientists and Engineers Conference and Exhibition 2014: Experience the Energy - Incorporating SPE EUROPEC 2014 ; 19 June , 2014 , pp. 1031-1035 ; Ahadian, M. M ; Taghikhani, V ; Sharif University of Technology
2014
Abstract
The diffusion and deposition of TiO2 nanoparticles in EOR application was investigated in this paper. TEM image of nanoparticles showed that the particles are elongated with average long and short axis sizes of 54 and 15 nm. Water flooding tests showed that the recovery factor can be improved from 49% to 80% using TiO2 nanoparticles. Viscosity and interfacial tension measurements showed that by using TiO2 nanoparticles the viscosity of injected fluid and interfacial tension do not change significantly and can not explain the change in recovery factor. Contact angle measurements showed that nanoparticles deposition changed the wettability of the rock surface from oil-wet to water-wet. SEM...
Modeling of CO2 solubility in brine by using neural networks
, Article Saint Petersburg 2012 - Geosciences: Making the Most of the Earth's Resources, 2 April 2012 through 5 April 2012 ; April , 2012 ; Salami, H ; Taghikhani, V ; Sharif University of Technology
European Association of Geoscientists and Engineers, EAGE
2012
Abstract
CO2 sequestration in geological formations, such as aquifers, is known to be the best short-term solution to CO2 mitigation. Accurate description of CO2 solubility in brine is important for evaluating the capacity of aquifers to sequester CO2. Currently, EOS-based models are widely used in reservoir compositional simulators for this purpose. However, most of these models involve complex and iterative calculations which take too much time in case of large-scale flow simulation of geological CO2 storage. In this study, a neural network model is presented for prediction of CO2 solubility in brine which is highly accurate with less computational overhead
Enhanced heavy oil recovery using TiO2 nanoparticles: Investigation of deposition during transport in core plug
, Article Energy and Fuels ; Volume 29, Issue 1 , November , 2014 , Pages 1-8 ; 08870624 (ISSN) ; Ahadian, M. M ; Taghikhani, V ; Sharif University of Technology
American Chemical Society
2014
Abstract
Although application of nanoparticles in enhanced oil recovery has been reported, understanding the transport and retention of nanoparticles in the oilfield reservoir is still a crucial issue. In this research, behavior of low concentration of TiO2 nanoparticles in core plug porous media and the mechanism of increasing oil recovery were investigated. Flooding test with a concentration of 0.01% TiO2 nanoparticles showed improvement in sweeping heavy oil from 41% to 55%. Inductively coupled plasma results on the exiting effluent of the flooding test with a concentration of 0.05% TiO2 nanoparticles showed the presence of only 0.5% of injected nanoparticles, which indicates high affinity of the...
Modeling the Thermomechanical Behaviour of Shape Memory Materials Using Analytical and Numerical Methods
, M.Sc. Thesis Sharif University of Technology ; Karimi Taheri, Ali (Supervisor)
Abstract
Shape memory materials are a kind of smart materials which recently have been used in a wide range of fields in particular medicine and aerospace. These materials can be divided to shape memory polymers and shape memory alloys. The basis of shape memory alloys’ properties is a thermoelastic martensitic transformation taking place between a high symmetric phase, called Austenite, and a low symmetric phase, called Martensite. In this project, by means of finite element methods, continuum thermomechanics and selection of appropriate internal variables (such as amount and orientation of volumetric fraction of each phase) and control variables (like strain, stress, temperature and entropy), their...
A new model for predicting activity coefficients in aqueous solutions of amino acids and peptides
, Article Journal of Chemical Thermodynamics ; Volume 35, Issue 1 , 2003 , Pages 101-112 ; 00219614 (ISSN) ; Ghotbi, C ; Taghikhani, V ; Sharif University of Technology
2003
Abstract
A new two-parameter model based on the perturbation of a hard-sphere reference has been developed to correlate the activity coefficients of several amino acids and simple peptides in aqueous solutions. The hard-sphere equation of state used as the reference in the model was proposed recently by Ghotbi and Vera. The perturbation terms coupled with the reference hard-sphere equation of state are attributed to the dispersion forces and the dipole-dipole interactions. The Lennard-Jones and Keesom potential functions are used to represent the dispersion and dipole-dipole interactions, respectively. The results of the new model are compared with those obtained by other models. It is shown that the...