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wetting
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Phase field approach for nanoscale interactions between crack propagation and phase transformation
, Article Nanoscale ; Volume 11, Issue 46 , 2019 , Pages 22243-22247 ; 20403364 (ISSN) ; Levitas, V. I ; Farrahi, G. H ; Javanbakht, M ; Sharif University of Technology
Royal Society of Chemistry
2019
Abstract
The phase field approach (PFA) for the interaction of fracture and martensitic phase transformation (PT) is developed, which includes the change in surface energy during PT and the effect of unexplored scale parameters proportional to the ratio of the widths of the crack surface and the phase interface, both at the nanometer scale. The variation of these two parameters causes unexpected qualitative and quantitative effects: shift of PT away from the crack tip, "wetting" of the crack surface by martensite, change in the structure and geometry of the transformed region, crack trajectory, and process of interfacial damage evolution, as well as transformation toughening. The results suggest...
Microfluidic devices with gold thin film channels for chemical and biomedical applications: a review
, Article Biomedical Microdevices ; Volume 21, Issue 4 , 2019 ; 13872176 (ISSN) ; Rabiee, N ; Rabiee, M ; Bagherzadeh, M ; Tahriri, M ; Tayebi, L ; Hamblin, M. R ; Sharif University of Technology
Springer New York LLC
2019
Abstract
Microfluidic systems (MFS) provide a range of advantages in biomedical applications, including improved controllability of material characteristics and lower consumption of reagents, energy, time and money. Fabrication of MFS employs various materials, such as glass, silicon, ceramics, paper, and metals such as gold, copper, aluminum, chromium and titanium. In this review, gold thin film microfluidic channels (GTFMFC) are discussed with reference to fabrication methods and their diverse use in chemical and biomedical applications. The advantages of gold thin films (GTF) include flexibility, ease of manufacture, adhesion to polymer surfaces, chemical stability, good electrical conductivity,...
An atomistic insight into the implications of ion-tuned water injection in wetting preferences of carbonate reservoirs
, Article Journal of Molecular Liquids ; Volume 293 , 2019 ; 01677322 (ISSN) ; Badizad, M. H ; Ghatee, M. H ; Ayatollahi, S ; Sharif University of Technology
Elsevier B.V
2019
Abstract
The efficiency of water flooding methods is known to improve by applying ion-tuned water injection. Although there is a consensus that such improvement happens through reversing reservoir wettability characteristics to more water-wet state, the true impact of ions is still ambiguous among contradictory debates. The well-known molecular dynamics (MD) simulation techniques would shed light on such ambiguities to gain deep atomic-scale understanding of the process. Results from MD simulations show that the presence of Na+ and Cl¯ ions leads to the formation of an electrical double layer in adjacency of calcite surface while Mg2+ ions dominantly make complexes with hydrocarbons throughout the...
Wettability alteration of carbonate rock by nonionic surfactants in water-based drilling fluid
, Article International Journal of Environmental Science and Technology ; Volume 16, Issue 11 , 2019 , Pages 6547-6556 ; 17351472 (ISSN) ; Ramazani SaadatAbadi, A ; Jafari Behbahani, T ; Sharif University of Technology
Center for Environmental and Energy Research and Studies
2019
Abstract
The influx of solid or liquid particles of drilling mud into the pores of rock or mud loss phenomenon and clay swelling can sometimes lead to severe productive formation damage and cause to wettability alterations of reservoir rock from hydrophilic to oleophilic. Therefore, designing an appropriate fluid that is compatible with formation fluids and could reduce reservoir damage and increase the productivity of wells is very important. The two main mechanisms of surfactants are reduction of the surface tension and wettability alteration of rock reservoir that are effective in taking the oil. Regarding the importance of the wettability in reservoir productivity, this article is aimed to study...
A new insight into pore body filling mechanism during waterflooding in a glass micro-model
, Article Chemical Engineering Research and Design ; Volume 151 , 2019 , Pages 100-107 ; 02638762 (ISSN) ; Sadatshojaie, A ; Mohebbi, A ; Riazi, M ; Sharif University of Technology
Institution of Chemical Engineers
2019
Abstract
By displacing oil in porous media with other fluid, different mechanisms of fluid displacing occur. The importance of understanding the trapping mechanisms like pore body filling is irrefutable. Pore body filling mechanism with a coordination number of four has different events like I0, I1, I2 and I3. Previous studies showed that the event of I0 occurs when the pore is only filled by a compressible non-wetting phase, but this study showed that this event could also occur by an incompressible non-wetting phase. Trapping mechanisms can be examined in a glass micro-model. In this research, a glass micro-model with three different patterns was used. Results showed that at two spots of the...
Wettability alteration of oil-wet carbonate porous media using silica nanoparticles: Electrokinetic characterization
, Article Industrial and Engineering Chemistry Research ; Volume 58, Issue 40 , 2019 , Pages 18601-18612 ; 08885885 (ISSN) ; Ghazanfari, M. H ; Sharif University of Technology
American Chemical Society
2019
Abstract
Application of nanoparticles for wettability alteration offers a practical approach to resolve some surface-related problems encountered in the nowadays technological process. Examples are underground/subsurface engineering implications, including the enhanced oil recovery from the oil-wet carbonate reservoirs. However, the common wettability evaluating techniques such as contact angle and flotation cannot be representative of the dynamic phenomena occurring at the pore scale and hence are unable to give accurate information about the process. Therefore, in the present work, the electrokinetic evaluations are utilized to explore the wettability alteration of initially oil-wet carbonate rock...
Electrowetting induced droplet jumping over a bump
, Article Extreme Mechanics Letters ; Volume 32 , 2019 ; 23524316 (ISSN) ; https://www.sciencedirect.com/science/article/pii/S2352431619300410 ; Daeian, M. A ; Moosavi, A ; Shafii, M. B ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
We study electrowetting induced droplet jumping over a system consisting of a flat surface and a topographical bump mounted on the surface. Different bump shapes including triangular and elliptical configurations are considered and the results are compared with the results of the flat surface. The results indicate that droplet jumping is enhanced over the bumps and the droplet jumps to larger heights compared with the flat surface because of the lower viscous dissipation. The shape of the bump can considerably affect the droplet dynamics. Between the considered shapes the triangular bump provides a larger dynamic and the droplet on the surface with this bump can jump with larger velocity....
A new approach for preparation of semi-transparent superhydrophobic coatings by ultrasonic spray hydrolysis of methyltrimethoxysilane
, Article Progress in Organic Coatings ; Volume 135 , 2019 , Pages 248-254 ; 03009440 (ISSN) ; Sabour Rouh Aghdam, A ; Nazari, M ; Bayat, A ; Saievar Iranizad, E ; Sharif University of Technology
Elsevier B.V
2019
Abstract
A novel nebulizing spray hydrolysis approach was used for preparation of semi-transparent superhydrophobic coatings. Methyltrimethoxysilane was dissolved in water:ethanol mixture and ultrasonically sprayed on different substrates. Superhydrophobic coatings with a contact angle (CA) as high as 164° and a sliding angle below 5° were obtained. FESEM and AFM revealed a hierarchical micro-nano binary structure with nanometric roughness of the coatings. The coated glass substrate exhibited transmittance close to 80%. The prepared coating showed great self-cleaning and water jet repellency behaviors. The superhydrophobicity of the samples was remained after subjecting to ambient conditions for 50...
Interactions between Rock/Brine and Oil/Brine interfaces within thin brine film wetting carbonates: A molecular dynamics simulation study
, Article Energy and Fuels ; Volume 33, Issue 9 , 2019 , Pages 7983-7992 ; 08870624 (ISSN) ; Badizad, M. H ; Kargozarfard, Z ; Ayatollahi, S ; Sharif University of Technology
American Chemical Society
2019
Abstract
The thin brine film that wets rock surfaces governs the wettability of underground reservoirs. The ionic composition and salinity of this nanosized brine film influence the wetting preference of the rock pore space occupied by hydrocarbons. Despite numerous investigations over the last decades, a unanimous fundamental understanding that concerns the contribution of ions in the original wetting state of the reservoir is lacking and hence the mechanisms responsible for the wettability reversal of the mineral are still unclear. This wettability reversal is the main consequence of ion-Tuned waterflooding. Although the method is widely accepted in practice, there is no universal consensus on the...
Experimental investigation of the wetted surfaces of stepped planing hulls
, Article Ocean Engineering ; Volume 187 , 2019 ; 00298018 (ISSN) ; Nowruzi, H ; Karami, M ; Javanmardi, H ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
In the current study, experimental tests are conducted to evaluate the hydrodynamic characteristics and the bottom wetted surfaces of the planing hulls equipped by one transverse step. For this purpose, total resistance, dynamic trim angle, dynamic sinkage, reattachment lengths of the separated flow and forebody and aftbody wetted areas are quantitatively measured at different geometrical parameters of the step and hull velocities. Moreover, the bottom wetted surfaces are qualitatively investigated by analyzing the underwater photographs. Our experimental results are also compared by archival data with good accordance. Based on our experimental observations, dynamic trim angle and dynamic...
A comparative study of earthquake source models in high-order accurate tsunami simulations
, Article Ocean Modelling ; Volume 141 , 2019 ; 14635003 (ISSN) ; Bonev, B ; Hesthaven, J. S ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
The discontinuous Galerkin method is used to solve the non-linear spherical shallow water equations with Coriolis force. The numerical method is well-balanced and takes wetting/drying into account. The two fold goal of this work is a comparative study of dynamic and static tsunami generation by seabed displacement and the careful validation of these source models. The numerical results show that the impact of the choice of seabed displacement model can be significant and that using a static approach may result in inaccurate results. For the validation of the studies, we consider measurements from satellites and buoy networks for the 2011 Tohoku event and the 2004 Sumatra–Andaman tsunami. The...
Investigation of fuel dilution in ethanol spray MILD combustion
, Article Applied Thermal Engineering ; Volume 159 , 2019 ; 13594311 (ISSN) ; Mardani, A ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
MILD combustion is a promising technique for low heating value fuels. In this paper, spray MILD combustion of diluted liquid fuel is numerically studied. The modelling framework is based on the RANS approach, the EDC combustion model with a skeletal chemical mechanism, and the Lagrangian tracking of droplets. The validated numerical model is used to simulate the combustion of ethanol diluted with water is studied for different oxidizer temperatures and O2 concentrations under MILD condition. Results indicate that a low-level fuel dilution up to 5 percent has tendency toward expansion of MILD region, but higher degrees fuel dilution within the range of 5–20 percent results in a reduction of...
The role of surface wettability on the heat transfer in liquid-liquid two-phase flow in a microtube
, Article Physics of Fluids ; Volume 31, Issue 8 , 2019 ; 10706631 (ISSN) ; Kazemzadeh Hannani, S ; Farhanieh, B ; Sharif University of Technology
American Institute of Physics Inc
2019
Abstract
Liquid-liquid two-phase flow is capable of boosting heat transfer in microdevices compared to the single-phase and gas-liquid flows. A thorough investigation is performed here to characterize the heat transfer in water-oil flow in a microtube. Finite element method along with the level-set model is employed for numerical simulation. A main part of this paper is devoted to studying the effect of wettability on the heat transfer performance. Four contact angles of 0°, 30°, 150°, and 180° are investigated, which revealed that the contact angle of 150° produces the highest Nusselt number (Nu). Triple points form at this contact angle, and the slugs slide on the wall, which results in more...
On the size-dependent behavior of drop contact angle in wettability alteration of reservoir rocks to preferentially gas wetting using nanofluid
, Article Journal of Petroleum Science and Engineering ; Volume 178 , 2019 , Pages 1143-1154 ; 09204105 (ISSN) ; Ghazanfari, M. H ; Dehghan Monfared, A ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Wettability alteration of rock surfaces toward gas wetting have been recognized as a practical approach for maximizing the production from the gas condensate reservoirs. Most of the reported work in this area applied the so called sessile drop contact angle measurement technique to examine the change in wetting state of a surface. However, the size-dependent wetting behavior of drop which could affect the exact determination of wettability and wettability changes was not well discussed in the previous studies. Therefore, in this work, the size dependency of contact angle for four different liquid-solid-gas systems; i.e., water-calcite-air, water-treated calcite-air (nanofluid treated...
Electrowetting-induced droplet jumping over topographically structured surfaces
, Article Materials Research Express ; Volume 6, Issue 8 , 2019 ; 20531591 (ISSN) ; Moosavi, A ; Shafii, M. B ; Sharif University of Technology
Institute of Physics Publishing
2019
Abstract
We analyze the process of electrowetting-induced jumping of droplets away from a substrate with a geometric heterogeneity in the form of a cone and compare the results with those of a flat substrate in different wettabilities and hydrophobicities. Our results reveal that the droplet dynamics can be enhanced through applying a topographic heterogeneity. However, increasing the height of the cones does not always provide a better condition for the jumping and there is an optimum value for the height of the cones. The enhancement is due to the fact that more liquid flowing affects the pressure gradient within the droplet leading to a higher jumping velocity. It is shown that for the flat...
Investigating fluid invasion control by Colloidal Gas Aphron (CGA) based fluids in micromodel systems
, Article Journal of Natural Gas Science and Engineering ; Volume 66 , 2019 , Pages 1-10 ; 18755100 (ISSN) ; Kamari, E ; Kazemzadeh, E ; Ghazanfari, M. H ; Soleymani, M ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Recently, Colloidal Gas Aphron (CGA) based fluids have been introduced to further develop depleted hydrocarbon reservoirs. This fluid system has been employed in an attempt to control drilling fluid invasion and, thus, reducing formation damage occurred during drilling operations. Understanding the mechanisms of fluid invasion control is of great importance for successful design and application of CGA-based fluids in drilling operations. Although fluid flow of conventional foams has been studied extensively in the available literature, little attention has been paid to CGA fluids flow, especially in heterogeneous fractured porous media. Here, an experimental study was conducted to achieve...
Effect of salinity and ion type on formation damage due to inorganic scale deposition and introducing optimum salinity
, Article Journal of Petroleum Science and Engineering ; Volume 177 , 2019 , Pages 270-281 ; 09204105 (ISSN) ; Riahi, S ; Ayatollahi, S ; Mokhtari, R ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Smart water injection is recognized as an effective EOR process to alter the wettability and interfacial tension to obtain higher micro/macro sweep efficiencies. This water contains reactive ions such asMg2+, Ca2+ andSO42- which can act as potential-determining ions and change the surface charge of calcite rocks. One of the major concerns in the execution of an effective water-flood process, especially in tight carbonate reservoirs, is the chemical incompatibility between the formation brine and the injecting water. In the present study, laboratory fluid compatibility tests were carried out and software simulation was done to investigate the most important challenges of the water-flooding...
Impact of ionic composition on modulating wetting preference of calcite surface: Implication for chemically tuned water flooding
, Article Colloids and Surfaces A: Physicochemical and Engineering Aspects ; Volume 568 , 2019 , Pages 470-480 ; 09277757 (ISSN) ; Badizad, M. H ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Despite previous researches on ion-engineered waterflooding (IEWF), its underlying mechanisms are not fully understood, particularly in presence of additives, like surfactants. This paper concerned with the contribution of Ca 2+ , Mg 2+ , SO 4 2- and Na + into altering wettability of oil-wet carbonate minerals towards water preferred state. As a mechanistic study, an experiment workflow was conducted to probe the impact of ions' concentrations in SW, either with or without sodium dodecylbenzene sulfonate (SDBS) which is an anionic surfactant. At first, contact angle (CA) measurement was carried out to evaluate the degree of wettability reversal upon treating the oil-aged calcite slabs with...
Simulating imbibition process using interacting capillary bundle model with corner flow: The role of capillary morphology
, Article Journal of Petroleum Science and Engineering ; Volume 176 , 2019 , Pages 62-73 ; 09204105 (ISSN) ; Khasi, S ; Ghazanfari, M. H ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Interacting capillary bundle model has been much attended for modeling of imbibition process, however, how the tube morphology controls the front displacement is not well discussed in the available literature, especially when corner flow of wetting phase is considered. Tubes with non-circular cross-sections were used for simulating imbibition process performed on drained bundle of tubes. Different combinations of the interacting tubes with equilateral triangular, square, and circular cross sections were used in the bundle model to explore the role of capillary morphology. The evolution of displacement front, as well as transient water saturation profiles along the model, were obtained for...
Development of a novel graphene oxide-blended polysulfone mixed matrix membrane with improved hydrophilicity and evaluation of nitrate removal from aqueous solutions
, Article Chemical Engineering Communications ; Volume 206, Issue 4 , 2019 , Pages 495-508 ; 00986445 (ISSN) ; Nasseri, S ; Mahvi, A. H ; Nabizadeh, R ; Mousavi, S. A ; Maleki, A ; Alimohammadi, M ; Jafari, A ; Hemmati Borji, S ; Sharif University of Technology
Taylor and Francis Ltd
2019
Abstract
In this study, four types of mixed matrix membranes were fabricated using polysulfone (as the base polymer) and different contents of graphene oxide (GO) nanosheets (as modifier) through wet phase inversion method. Based on the amounts of GO (0, 0.5, 1, and 2 wt%), the synthesized membranes named as M1, M2, M3, and M4, respectively. The membranes characteristics were evaluated using FE-SEM, FT-IR, and water contact angle measurements. In addition, the performance of the prepared membranes was investigated in terms of basic parameters: filtrate water flux, nitrate removal efficiency, and antifouling properties. Results showed significant improvements of the characteristics of modified...