Sharif Digital Repository

Permeability is an essential parameter used for reservoir evaluation, simulation and management to optimize oil recovery. The conventional approach to estimate reservoir connectivity, conductivity, sweep efficiency and other critical information for decision-making is to build detailed geological models, which are then upscaled to a coarser grid where flow simulations are run. However, this takes many hours to be carried out even for a single realization practically. In practice, a very small number of realizations are considered and consequently the true uncertainty in the results is very poorly estimated. In this study, a statistical model of isotropic overlying sandbodies is used to... 

The purpose of this research project was to improve the performance of TEG liquid membrane in separation of gas mixtures by adding zeolite LTA nanoparticles. Therefore, the NaA zeolite particles with nano size were synthesized with hydrothermal method at optimized condition. The supported liquid membrane with hydrophilic PVDF membrane and triethylene Glycol (TEG) was prepared in two different conditions. In the first one, the pores of the supporting membrane were filled with triethylene Glycol, whereas in the second one the pores were filled with the mixture of triethylene Glycol along with the 5 wt% and 10 wt% zeolite nanoparticles. The performances of prepared membranes were investigated... 

Real modeling of ceramic foam filters, because of their specific tortuosities is not possible and in case of possibility of real modeling of pores in filters, because of restriction of element’s dimensions, the number of elements increases and model can’t be run in a reasonable time with common computers which are accessible nowadays. The common computer simulation of filters in Computational Fluid Dynamic (CFD) and their effect on fluid flow pattern is done by use of permeability properties of porous media. In this research, ceramic foam filters which are used in casting are simulated by Forchhimer and Darcy models. SUT CAST software is used for simulation, because of its ability for... 

Polymeric membranes based on polyaniline and PVDF were prepared by using cast-solvent film method. The effects of various parameters including polyaniline synthesis temparature, thickness of the PANI/PVDF films and feed pressure were investigated. The results obtained from exprimental data showed increasing permeability with reducing the thickness of the film and increasing feed pressure. Increasing polyaniline synthesis temprature increased the permeability of PANI/PVDF films. Reducing the films thikcness and increasing the feed pressure decreased the selectivity of films for the , and . The results showed increasing selectivity for PANI/PVDF films by using PANI produced at 10°C.... 

In this work, the effect of chemical composition on structural, mechanical, electrical and magnetic properties of nanocrystalline Finemet-type alloys with the composition of Fe73.5Si13.5B9Nb3Cu1 , Fe77Si11B9Nb2.4Cu0.6 and (〖Fe_0.5 Co_0.5)〗_77 Si_11 B_9 Nb_2.4 Cu_(0.6 )was investigated. The samples were prepared by vacuum arc melting of high purity constitution in order to obtain a nanocrystalline structure. The amorphous ribbons were then annealed under vacuum with the same conditions of temperatures and time to compare their properties. The structural and thermal properties of the samples were analyzed using various techniques such as X-ray Diffraction (XRD) and Differential Scanning... 

Aqueous phase trapping (APT) in many of the oil and gas reservoirs is a significant mechanism of formation damage during drilling, completion, work over, and stimulation operation. APT can limit the productivity of the well to a high extent, especially in low permeable gas reservoirs. Experimental investigation of factors affecting APT is vital to recognize extends of associated damage and contribution of each factor. Albeit many experimental studies have been conducted as regards factors affecting removal of phase traps in understudy mechanism of formation damage, but up to date no experimental data has been published regarding effect of different factors on reservoir’s potential for APT.... 

Matrix acidizing treatment are performed to enhance the permeability of oil and gas formations by removing pore plug. Numerous additives have been introduced to aid the penetration of the acid or to perform other important tasks. To be able to pump the reactive fluid from the surface through the tubing and into the formation, corrosion inhibitors usually is necessary to protect the metal from attack by the fluid itself. In this work the Henna extract introduced as a pre flush additive and corrosion inhibitor in acidizing operation. It also enters the formation and effect on the matrix permeability and acidizing performance. The effect of Henna extract on permeability of rock will be... 

Excavation of metro tunnel beneath groundwater level causes disturbance of hydro geological balance and change in stress conditions at its environment. One of the usual methods of the tunnel construction is utilizing tunnel boring machine and one of the most important of them is called TBM-EPB which takes advantage of the earth pressure balance method. Control of surface settlements which is a result of creating underground space in urban area is a matter of great importance and is influenced by various parameters. This thesis has tried to investigate factors such as geotechnical properties among cohesion, internal friction angle, elasticity modulus, permeability and porosity and also... 

Porous Asphalt or Porous Friction Courses (PFCs) are mainly recommended as surface drainage layers on rainy runway pavements and roads with medium traffic. Characteristic features of porous asphalt mixes are improved permeability, skid resistance and sound attenuation. The purpose of this research is to evaluate the effect of mixture parameters such as binder content, amount of modifier and aggregate gradation on the performance and durability of the porous mixtures. In this research ground tire rubber was used as the modifier. Mechanical properties of these mixes were assessed by determining stone-on-stone condition, Marshall stability, unaged abrasion loss, and aged abrasion loss tests.... 

Increasing use of polymeric materials, especially in the packaging industry, besides the problems that exist in recycling these materials, has become a serious concern for the environment. The synthetic polymers are used widely in packaging industry so they have a considerable role in waste production in packaging industry. One way to solve this problem is adding a natural polymer to the synthetic polymer, as a result it becomes friendly environmentally. Starch is one of these natural polymers which is cheap and has the ability to complete degradation in the environment.using row starch in the polymeric compounds causes a severe drop in compound’s properties. For this reason, row starch must... 

The success of oil recovery depends, among other factors, on the ability to provide reliable simulations of the reservoir performance. The reservoir dynamics are usually modeled by a distributed parameter dynamic system whose parameters represent the petrophysical properties of the reservoir. A proper characterization of those reservoir properties is fundamental for an accurate reservoir simulation. The petrophysical properties are highly heterogeneous and only a limited number of measurements are available at certain locations in the reservoir. Therefor, in ordet to obtain accurate prediction of the reservoir performance, it is essential to possess reliable estimates of the petrophysical... 

Open graded asphalt mixturesareasphaltic mixes used in flexible pavements and the mainadvantages of them are increased permeability and noise reduction. Conventional application of these mixtures in flexible pavement is like that fluids infiltrate into porous asphalt layer that places over a dense graded asphalt layer and then draintoward ditches along the two sides of the road. Another usage of these mixtures, considered in recent years, is in porous pavements that the structure permits water on the surface topass freely through it and to infiltrateinto thesubsoil. In this research, second application of open graded asphalt mixtures is considered, i.e., porous asphalt pavement. In this type... 

In the first part of this thesis, limitations on magnetic field distribution are studied. After that methods of creating high gradient magnetic field and limitations on it is discussed. In the second part, magnetic properties of materials and the effect of particle shape and size on these properties are studied. In this part a comprehensive analysis on demagnetizing field inside magnetic bodies is also conducted and its dependence on material susceptibility and shape is discussed. At the end of this part the effect of particle shape and size on its hysteresis loop is demonstrated theoretically, practically and by computer simulation. In order to ... 

Fuel Cell with Polymer membrane uses a reaction with Hydrogen and Oxygen as reactants to produce electricity. As the product of this reaction is water, this fuel cell produce clean energy. But if the produced water accumulates it can cause problems for fuel cell which can lead to complete failed of fuel cell. On the other hand water shortage in PEM fuel cell also can cause problems. So we need to have continues water management inside of PEM fuel cell. For this sake having knowledge about water inside of PEM fuel cell and specially the Gas Diffusion Layer which is the layer with responsibly to help the fuel cell to manage the water, is necessary. One of the ways for gaining that knowledge... 

This work concerns with experimental and modeling investigation of the asphaltene damage removal using ultrasonic wave irradiation. A specific core holder apparatus was designed and utilized for in situ ultrasonic exposure to damaged core plug at different conditions of exposure time, ultrasound power and distances between sound source and plug. Injection of many pore volumes of an asphaltenic crude oil was used for creating asphaltene induced damaged in porous media through permeability measurements. The deposited asphaltene during oil injection as well as asphaltene removal due to ultrasonic exposure was evaluated using IP-143 analysis. The results revealed that ultrasound application... 

Fracture and Matrix permeability systematically change because production time of gas and oil reservoirs is very long and pore pressure, temperature and in-situ stresses continously change in reservoirs.This parameters have an important role in determination and development of wells according to the permeability distribution.The main factors in determination of fracture permeability values is normal and shear stiffness that parameters such as roughness, opening, closure, aperture and asperities influence this factor.In this thesis, we try to investigate the influence of this parameters on fracture permeability according to the normal and shear stresses.Also we want to investigate the... 

Because of higher hydrogen demand in recent years, study of hydrogen separation from gas mixtures is highly regarded. Because of some parameters such as high surface to volume ratio and ability to withstanding high pressure, polymeric hollow fiber membranes have a good potential of hydrogen recovery. So in this study, fabrication of single-layer and dual-layer hollow fiber membranes have been investigated. Selective polymer that used in both single and dual layer membranes is polyethersulfone. Membranes were fabricated by dry-wet phase inversion method and effects of extrusion rates and their ratio, composition and temperature of polymer solution, composition of bore fluid, coating and air... 

The application of acoustic waves as a diagnostic tool in medicine is highly regarded. Because of the mechanical and Noninvasive nature of this waves when penetrate in the body will not have any adverse effects on the body. Thus development and operation of these waves is growing every day. If abnormal changes in soft tissues (such as tumors inside the body) is created, by the reflected sound waves easily recognizable although it is experimental, and a little scientific studies have been conducted on the contrast of soft tissue and acoustic waves. Soft tissues of the human body Because of the asymmetric structure has a non-uniform physical and mechanical properties in different directions,... 

Characteristic of the reservoir, including the important discussion in the oil industry, is widely practiced in the modeling, simulation and EOR. One of the methods fordetermining the specifications of the reservoir is geostatistical technique. This means that a large number of realizations of the reservoir model to assess the uncertainty in reservoir descriptions of performance predictions should be made.However flow simulation of all these realizations is very difficult due to cost and time calculations.To mend the problem, we use ranking realization that finally a minor number of realizations are selected and flow simulation is used to them.In this project, we use streamline simulation to... 

Acidizing efficiency depends on various factors such as formation properties, reservoir and stimulation fluid types and injection scenario. Among these factors, heterogeneity of reservoir’s formation (layered reservoirs and permeability variation versus depth) strongly affect acidizing performance. Accordingly, applying a reliable technique that distribute stimulation fluid uniformly is essential. The aim of carbonate matrix acidizing is to improve fluid flow specially in low permeability zones. Stimulation fluid cannot enter into the low permeability layer due to existence of high permeability layers which are in contact with low permeability ones. So, the stimulation fluid should be...