Search for: interfacial-property
Investigation of Dynamic Behavior of Interface by Simulation of New Experimental Method, M.Sc. Thesis Sharif University of Technology ; Bastani, Dariush ; Safekordi, Ali Akbar ; Lotfi, Marzieh
Surface phenomena and dynamic Interfacial properties play an important roles in gas- liquid and liquid-liquid multiphase process from various industrial applications to understand fundamental phenomena. However, there is no experimental equipment and efficient methods for quantitative and detail investigation of interfacial properties under fast and non-equilibrium dynamic condition due to mobility and refreshing of interface (such as rising bubble). Also existing models accompanied with a lot of simplifications which is not yet validated with a proper experimental data. development of laboratory equipment base on measuring momentary capillary pressure and presenting a new experimental...
A thermoelasticity solution of sandwich structures with functionally graded coating, Article Composites Science and Technology ; Volume 67, Issue 6 , 2007 , Pages 1073-1080 ; 02663538 (ISSN) ; Haftbaradaran, H ; Asghari, M ; Sharif University of Technology
An exact thermoelasticity solution for a two-dimensional thick composite consisting of homogeneous and functionally graded layers is presented. The thermomechanical properties of functionally graded layers are assumed to vary exponentially through the thickness while the Poisson's ratio is taken to be constant. The heat transfer problem is solved under steady state condition accounting for the heat convection. Utilizing the stress function the governing equation reduces to a fourth order inhomogeneous partial differential equation which is solved exactly using Fourier series method. A comparative study is done between two sandwich structures with homogeneous and functionally graded coatings,...
Investigation of the interphase effects on the mechanical behavior of carbon nanotube polymer composites by multiscale modeling, Article Journal of Applied Polymer Science ; Volume 117, Issue 1 , March , 2010 , Pages 361-367 ; 00218995 (ISSN) ; Naghdabadi, R ; Sharif University of Technology
In this article, a multiscale modeling procedure is implemented to study the effect of interphase on the Young's modulus of CNT/polymer composites. For this purpose, a three-phase RVE is introduced which consists of three components, i.e., a carbon nanotube, an interphase layer, and an outer polymer matrix. The nanotube is modeled at the atomistic scale using molecular structural mechanics. Moreover, three-dimensional elements are employed to model the interphase layer and polymer matrix. The nanotube and polymer matrix are assumed to be bonded by van der Waals interactions based on the Lennard-Jones potential at the interface. Using this Molecular Structural Mechanics/Finite Element...
Experimental investigation of the influence of fluid-fluid interactions on oil recovery during low salinity water flooding, Article Journal of Petroleum Science and Engineering ; Volume 182 , 2019 ; 09204105 (ISSN) ; Ayatollahi, S ; Fatemi, M ; Sharif University of Technology
Elsevier B.V 2019
This study aims to investigate the role of fluid-fluid interactions during low salinity water flooding, using crude oil from an Iranian oil reservoir. To minimize the effects of mineral heterogeneity and wettability alteration, a synthetic sintered glass core was utilized and all coreflooding experiments were performed at low temperatures without any aging process. The effect of fluid-fluid interactions were investigated in both secondary and tertiary injection modes. pH measurements as well as UV-Vis spectroscopy and interfacial tension (IFT) analysis were performed on the effluent brine samples. Results: show that fluid-fluid interactions, mainly the dissolution of crude oil polar...
Low salinity injection into asphaltenic-carbonate oil reservoir, mechanistical study, Article Journal of Molecular Liquids ; Volume 216 , 2016 , Pages 377-386 ; 01677322 (ISSN) ; Riazi, M ; Hajibagheri, F ; Ayatollahi, S ; Sharif University of Technology
The impacts of salinity adjustment of displacing fluid have recently gained special attention to enhanced oil recovery (EOR). Different mechanisms have been studied widely in the literature while some of them are still subjugated to more scrutiny. The effects of diluted sea water on the interfacial properties of brine and asphaltenic-acidic crude oil and the wettability alteration of carbonate reservoir rock are investigated in this experimental observational work. The measurements of interfacial tension (IFT) and contact angle (CA) as two main parameters are studied. Besides, the effects of asphaltene and resin in the crude oil on the IFT values between the crude oil and aqueous solution...
Evaluation of effect of temperature and pressure on the dynamic interfacial tension of crude oil/aqueous solutions containing chloride anion through experimental and modelling approaches, Article Canadian Journal of Chemical Engineering ; 2017 ; 00084034 (ISSN) ; Ayatollahi, S ; Sharif University of Technology
Wiley-Liss Inc 2017
The interfacial properties of crude oil are highly complex and are not yet well understood. This study aimed to evaluate the effect of temperature (30-80°C) and pressure (3.44-27.58MPa) on the dynamic interfacial tension (IFT) of crude oil/aqueous solutions consisting of 15000ppm of salt containing different chloride anions, e.g. NaCl, KCl, MgCl2, and CaCl2. To reach this goal, several parameters, such as dynamic and equilibrium IFT, adsorption time, diffusivity of resin, and asphaltene as surface-active agents from bulk of crude oil towards fluid/fluid interface and surface excess concentration of them at the interface, were compared as a function of temperature, pressure, and ion type. The...
Evaluation of effect of temperature and pressure on the dynamic interfacial tension of crude oil/aqueous solutions containing chloride anion through experimental and modelling approaches, Article Canadian Journal of Chemical Engineering ; Volume 96, Issue 6 , 2018 , Pages 1396-1402 ; 00084034 (ISSN) ; Ayatollahi, S ; Sharif University of Technology
Wiley-Liss Inc 2018
The interfacial properties of crude oil are highly complex and are not yet well understood. This study aimed to evaluate the effect of temperature (30–80 °C) and pressure (3.44–27.58 MPa) on the dynamic interfacial tension (IFT) of crude oil/aqueous solutions consisting of 15 000 ppm of salt containing different chloride anions, e.g. NaCl, KCl, MgCl2, and CaCl2. To reach this goal, several parameters, such as dynamic and equilibrium IFT, adsorption time, diffusivity of resin, and asphaltene as surface-active agents from bulk of crude oil towards fluid/fluid interface and surface excess concentration of them at the interface, were compared as a function of temperature, pressure, and ion type....
Thermophysical interface properties of crude oil and aqueous solution containing sulfate anions: experimental and modeling approaches, Article Petroleum Science and Technology ; Volume 37, Issue 21 , 2019 , Pages 2167-2173 ; 10916466 (ISSN) ; Ayatollahi, S ; Sharif University of Technology
Taylor and Francis Inc 2019
Sulfate anion is well-known for being one of the most active agents to be injected into the oil reservoirs and being capable of not only altering the interfacial properties of crude oil but also enhancing the water solution properties in oil recovery. In the current study, the effects of temperature and pressure were studied on interfacial tension (IFT) as well as the adsorption behavior of two different solutions containing sulfate anion using experimental measurements and modeling approaches. Although it was expected that IFT values of the studied systems might decrease as temperature increased due to the improvement in the molecule mobility and solubility of crude oil in water, which...
An atomistic insight into interfacial properties of brine nanofilm confined between calcite substrate and hydrocarbon layer, Article Applied Surface Science ; Volume 490 , 2019 , Pages 89-101 ; 01694332 (ISSN) ; Badizad, M. H ; Ayatollahi, S ; Sharif University of Technology
Elsevier B.V 2019
Molecular dynamics simulation was applied in this study to scrutinize the interfacial properties of water nano-film confined between calcite mineral and hydrocarbon layer, as two intrinsically different media. Such system resembles the environment experienced by water molecules in the pore spaces of underground carbonate reservoirs. The interplay between water film and confining phases, oil and mineral, strongly influences hydrocarbon production process; however, there is a lack of detailed understanding of the involved interactions. MD simulations indicate development of several layers with different water densities in the confined brine. Water molecules form well-ordered structure in three...
Effects of salinity, ion type, and aging time on the crude oil-brine interfacial properties under gravity condition, Article Journal of Petroleum Science and Engineering ; Volume 195 , December , 2020 ; Akhlaghi Amiri, H. A ; Ayatollahi, S ; Sharif University of Technology
Elsevier B.V 2020
In this study, the impacts of salinity, ion type, and aging process were investigated on coalescence and spreading of crude oil interfaces (including an oil droplet and an oil film) under gravity, through drop rest time measurement techniques, aided by an image analysis system. Three different salt solutions of NaCl, Na2SO4, and MgCl2 were studied at different ionic strengths, ranged from 1% to 150% of Persian Gulf seawater ionic strength. According to the results, aging the oil droplet in the brine increased the interfacial rigidity. Addition of a gas phase - by thinning the surface oil film - almost doubled both rest time and spreading time values. In the aged mode, the presence of salt in...
Rheology of interfacial layers, Article Current Opinion in Colloid and Interface Science ; Vol. 19, issue. 6 , 2014 , pp. 514-519 ; ISSN: 13590294 ; Lotfi, M ; Kragel, J ; Javadi, A ; Bastani, D ; Miller, R ; Sharif University of Technology
Dilational and shear viscoelasticities are important properties of interfacial layers. These quantities are particularly relevant in all systems which contain a huge internal interfacial area such as foams and emulsions. Therefore, also the 3D rheological behavior of foams or emulsions studied by respective methods is superimposed by the 2D interfacial rheology.We report on recent developments in dilational and shear rheology from an experimental point of view as well as discuss the state of the art of the underlying theories. Examples of most relevant experiments are also presented and discussed. Although not yet extensively investigated, the links between bulk rheology of foams and...
Bacteria cell hydrophobicity and interfacial properties relationships: A new MEOR approach, Article Colloids and Interfaces ; Volume 5, Issue 4 , 2021 ; 25045377 (ISSN) ; Javadi, A ; Jahanbani Veshareh, M ; Ayatollahi, S ; Miller, R ; Sharif University of Technology
For microbial enhanced oil recovery (MEOR), different mechanisms have been introduced. In some of these papers, the phenomena and mechanisms related to biosurfactants produced by certain microorganisms were discussed, while others studied the direct impacts of the properties of microorganisms on the related mechanisms. However, there are only very few papers dealing with the direct impacts of microorganisms on interfacial properties. In the present work, the interfacial properties of three bacteria MJ02 (Bacillus Subtilis type), MJ03 (Pseudomonas Aeruginosa type), and RAG1 (Acinetobacter Calcoaceticus type) with the hydrophobicity factors 2, 34, and 79% were studied, along with their direct...
Influence of surface-modified nanoparticles on the hydrodynamics of rising bubbles, Article Chemical Engineering and Technology ; Volume 44, Issue 3 , 2021 , Pages 513-520 ; 09307516 (ISSN) ; Bastani, D ; Lotfi, M ; Miller, R ; Sharif University of Technology
Wiley-VCH Verlag 2021
Local velocities of bubbles rising in four different nanosilica solutions were investigated experimentally. Also, the density, viscosity, and surface tension of fumed nanosilica and modified nanosilica solutions were measured. Heat treatment and chemical functionalization were used to modify the properties of silica nanoparticles. It was found that the addition of nanosilica affected the hydrodynamics of the rising bubble by increasing the drag friction at the interface. However, environmentally responsive nanosilica particles behaved like surfactant molecules, due to the interfacial activity of hydrophilic and hydrophobic chains. Silica nanoparticles coated with both hydrophilic and...
Enhanced oil-in-water droplet generation in a T-junction microchannel using water-based nanofluids with shear-thinning behavior: A numerical study, Article Physics of Fluids ; Volume 33, Issue 1 , 2021 ; 10706631 (ISSN) ; Shamloo, A ; Kazemzadeh Hannani, S ; Sharif University of Technology
American Institute of Physics Inc 2021
Nanofluids are widely used as the continuous phase during droplet formation in microsystems due to their impressive features such as excellent thermal, magnetic, and interfacial properties. Although it is well-known that nanofluids are susceptible to exhibit non-Newtonian behavior even at a low concentration of nanoparticles, effects of non-Newtonian behavior of nanofluids have not been studied on droplet formation thus far. In this study, oil-in-water droplet formation with a relatively high viscosity ratio of the immiscible phases was studied numerically in a T-junction microchannel. To inspect the non-Newtonian effects of aqueous nanofluids on droplet formation, empirical data on the...
Nanotechnology-assisted EOR techniques: New solutions to old challenges, Article Society of Petroleum Engineers - SPE International Oilfield Nanotechnology Conference 2012 ; 2012 , Pages 382-396 ; 9781622761104 (ISBN) ; Zerafat, M. M ; Sharif University of Technology
Enhanced Oil Recovery techniques are gaining more attention worldwide as the proved oil reserves are declining and the oil price is hiking. Although many giant oil reservoirs in the world were already screened for EOR processes, the main challenges such as low sweep efficiency, costly techniques, possible formation damages, transportation of huge amounts of EOR agents to the fields especially for offshore cases, analyzing micro-scale multi-phase flow in the rock to the large scale tests and the lack of analyzing tools in traditional experimental works, hinder the proposed EOR processes. Our past experiences on using nanotechnology to the upstream cases, especially EOR processes, revealed...