Sharif Digital Repository

Given the broad role of oil and gas playing in the world economy, finding the hydrocarbon reservoir that economically is affordable is quite significant. Some of the unconventional oil and gas reservoirs are important from the economic point of view since they produce insufficient hydrocarbon due to either low permeability or damage during drilling and production. Hydraulic fracturing is one of the most significant methods for improving the productivity of wells and reservoirs. Hydraulic fracturing acts by affecting on reservoir rock physic. In the current century, this approach has an essential effect in enhancing the permeability and production of reservoirs by creating, extending and... 

Optimizing and improving the design of wells will have significant impact on any recovery method. As for horizontal wells, despite the fact that horizontal wells improve reservoir access, they suffer from significant pressure loss as well as limited flow control locations and flow control and management. In addition, reservoir quality varies along the length of the well and in the reservoir. This will add further complexity and challenge in well control and production optimization. The design of completions plays a significant role in improving the productivity of a well as well as the life of the reservoir. Intelligent or smart completions can be used to monitor, evaluate and manage the... 

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... 

An important step in the early stages of an oilfield development is the accurate identification of the location of production and injection wells which has a significant impact on productivity and profitability of the reservoir. Recently, operation companies in petroleum industry focus on production optimization, recovery enhancement and cost reduction; as a result, application of non-conventional wells (NCW) or non-vertical wells have dramatically increased. Well placement optimization is a complicated task as it is a function of several contributing factors including reservoir heterogeneities and economic constraints. The complexity of this task increases when it is considered as a... 

In oil industry, increment of drilling mud viscosity is of great importance. Water based polymers are widely use as drilling fluid to achieve this goal. Formation damages can be occurred by invading polymer solution into the formation in different ways such as scale and precipitation. These damages appear in different shapes such as reduction in relative permeability and productivity index reduction. In this study we have proposed, designed and fabricated a novel device, called sand pack, to measure the damage of the reservoir which enable us to calculate relative permeability and recovery factor by means of pressure difference and flow rate. Using this lab-scaled device we have measured... 

An experimental study was conducted to investigate the reduction of relative permeability caused by salt precipitation. Series of isothermal sand pack flood experiments were conducted on a sand pack composed of several minerals and relative permeability of the involved phases were determined. This compose was taken south of Iranian reservoir properties. A stainless steel sand-pack of 2.5cm internal diameter and 19.2 cm long was designed and built for experimental procedure. There are is different methods to determine relative permeability of porous media, According to available facilities in the lab and objective of this study unsteady state have been chosen to determine relative... 

Constant drilling in the shale formation causes many problems such as shale swelling and well instability. Annually many costs are spent dealing with these problems in the drilling industry. Many factors can affect this issue. The most important factor is the type of drilling fluid and its additives. The use of oil-based mud is the best option to deal with the clays instability but, due to environmental problems resulting from OBM, their use has been banned in most parts of the world. Therefore, the water-based mud is the only option for the oil industry that can modify its property by use of additives. In this study, the muds contain Nano silica have been introduced. Silicate as shale... 

One of the three fundamental methods in reservoir evaluation is coring, other two methods are logging and well test. Coring is an operation during which, samples from formation rock are taken, and used for laboratory tests and examinations. Although coring presents exact information from reservoir rock, its small scale is the reason of some laboratory errors. This operation is fulfilled with special bits. Coring importance shines where it could give us an idea of reservoir conditions; however cannot be develop it, to all of the reservoir. Coring is used to identify rock properties like porosity, permeability, wettability and fluid properties like fluid density or fluid saturation. Rock... 

Given that the mean of the cost of drilling operation related to the required martials and preparation of the drilling fluids, therefore, the design and construction drilling fluid which omit has to be a proper rheology is essential in drilling operations and oil industry. A desirable property of the drilling fluid is the minimum fluid loss volume which can be achieved by formation of a low permeability filter cake on the wellbore. Drilling fluid filtrating invasion into the formation can cause formation damage and reduction in the productivity of the well. In drilling fluids, a series of natural synthetic and polymers may be used as fluid (filtration) loss control additives. However, high... 

Today due to increasing demand of using energy and petroleum products, finding optimum ways to produce more oil and gas in a way which petroleum reservoirs faces less pressure drop is very necessary. Therefore, petroleum engineers face multiphase flow proportionally more than other issues. So, they have to comprehend this issue in a complete manner in order to discover the best practical ways for maximum utilization. Researchers in different ways tried to model multiphase flow, but many of provided models are so complicated and sometimes have low accuracy. In this project we tried to present a model that in simplicity has high accuracy and works in a way that apperceiving it, is very... 

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... 

Alavand Oil field is located 50 Km away from west of Siri Island and includes DPG and DPH platforms. The production from Alavand field started in 1998 and till now 11 wells have been totally drilled .Since a production peak in 2001, the oil production in Alvand field has decreased. Water cut is increasing and reservoir pressure is decreasing gradually. Considering poor reservoir characteristic of this reservoir, productivity indexes of wells are relatively low. In addition; natural depletion of reservoir caused the wells to be unable to flow naturally and either closed or produce periodically consequently. To increase production and extend the lifetime of Alvand field, it is decided to start... 

Since the early 90s, nanotechnology has contributed to several developments in a wide range of Science and industry such as medicine, Physics, Chemistry, Aerospace, electronics and Biology. In recent years, nanotechnology has also made development in the oil and gas industry. The drilling fluid is already one of the most important parts in drilling operation.The physical properties of a mud, rheological properties and minimize fluid invasion into the formation with perfect mudcake are important to assist in optimizing results. Nano-materials as one of the achievements of recent years are effective in achieving these purposes. To obtain the above properties, a variety of polymers as... 

One of the major problems in directional and extended reach wells is poor hole cleaning. Directional and horizontal drilling is more complex than vertical wells. Ineffective particles transport leads to several undesirable issues during drilling. This thesis analyzed all parameters which have directly affected directional hole cleaning. The thesis is based on an experimental set-up designed in Sharif University. In the experimental work, two types of drilling fluid, Newtonian and Non-Newtonian with numerous rheological parameters, three different flow rate, three various nozzle sizes and three individual RPMs in three distinct inclinations 30°, 60° and 90° were used to simulate. Also, to... 

During the drilling process, cutting concentration in vertical and inclined wells is a common problem and major issue in designing hydraulic parameters. This is becoming more important in near bit area. Cutting transport usually is affected by several parameters such as mud rheology, flow rate, nozzle size, rotation speed, and mud weight.
In this work it was aimed to design a new set-up to test all the factors on hole cleaning phenomenon especially in near bit area. The set-up consists of a 16 feet long flow loop, 3.28 feet height of the test section, and 3.33 inches inner diameter of the test section. Each parameter which has an impact on hole cleaning could be varied. The cutting... 

Due to the suitable performance characteristics and the widespread use of Surface Piercing Propellers (SPPs) in high-speed crafts, many experiments and numerical studies have been conducted in this field. Due to the lack of a comprehensive series similar to conventional propellers in the field of SPPs, in this thesis, it has been tried to personalize the suitable basis by conducting two separate experimental tests in the National Iranian Maritime Laboratory (NIMALA) towing tank and the cavitation tunnel at Sharif University using computational fluid dynamics method and the commercial code STAR-CCM+. For this purpose, a wide range of phenomena and effective parameters on hydrodynamic... 

Problems with the mitral valve can make the heart less efficient at pumping blood around the body. Severe problems can lead to heart failure if the valve is not surgically repaired or replaced. A simple approximation of the heart geometry is used and the valve dimensions are based on reported measurements. The primary objective for this study is to design and simulate the opening and closing behavior of the mitral valve using 2D fluid-structure interaction (FSI) model using ADINA software in order to evaluate and investigate the hemodynamic performance and problems of mitral valve, in which the blood is described as a viscous incompressible fluid, and the mitral valve is described as an... 

In this thesis, the process of laser assisted machining (LAM) of metal matrix composites (MMC) is experimentally studied. The effects of process parameters (cutting speed, feed rate and depth of cut), laser parameters (laser power, laser frequency and laser beam angle), and the percentage of reinforcing particles on the tool wear and the surface roughness are investigated. Furthermore, the effects of these parameters on the built-up edge (BUE), chip shape, and workpiece temperature are explored.The experiments were performed using uncoated tungsten carbide and PCD tools under dry conditions. In order to analyze the sensitivity of the process parameters, the Plackett-Burman method was used... 

Cardiovascular diseases are the major cause of death worldwide. Atherosclerosis is one of the major types of cardiovascular diseases in which fibrous and fatty materials, called plaque, build up inside the artery and cause partial or total occlusion of the artery. Intravascular balloon angioplasty with or without stenting is the most common treatment of this disease. In 2010, approximately 954000 stent implantations were performed in the United States. The major issue associated with stenting is reclosure or renarrowing of the transverse section of the artery termed in-stent restenosis (ISR). Unfortunately, nearly one–third of the patients
who receive stent implantation require further... 

In the recent years, development of new technologies in the field of cognitive science has made a huge effect on the people social life style. Facial expression imitation with applications in the design of human robot interaction (HRI) systems is an active area of research. In this study, we propose an approach using a humanoid social robot, The Alice, for real-time imitation of human facial expression. The facial keypoints of the user are extracted by using the Kinect sensor together with manipulated SDK 2.0 codes. Kinect output array are collected for each expression, then the training dataset is created with these output arrays. An accurate Artificial neural network (ANN), which has a...