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nanofluidics
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Numerical Study of Heat Transfer Enhancement in Porous Medium by Applying Magnetic Field on Nano Fluid
, M.Sc. Thesis Sharif University of Technology ; Sadrhosseini, Hani (Supervisor)
Abstract
A 2D simulation has been carried out to study the effect of magnetic field on heat transfer and pressure drop of nanofluid flowing through a pipe filled with porous medium. The nanofluid flow is modeled as a single-phase flow, and Darcy–Brinkman–Forchheimer equation is employed to model fluid flow in porous media. A constant uniform heat flux was imposed on the walls of the cylinder, and the values of Darcy number, Hartmann number, and volume fraction of the nanoparticles were selected as 0.1, 200, and 0.2, respectively. Effects of parameters such as Reynolds number, the material of the porous medium (conductivity and porosity), and material of nanofluids have been investigated in the...
Study of Ion Transport from the Two-Dimensional Structure of MXene
, M.Sc. Thesis Sharif University of Technology ; Esfandiar, Ali (Supervisor)
Abstract
Reverse electrodialysis-based membranes are one of the most promising approaches to osmotic energy production. However, conventional reverse electrodialysis membranes have high strength and insufficient mass transfer, which leads to low power density and efficiency. In recent decades, the transport of ions at the nanoscale for the manufacture of reverse electrodialysis machines has attracted much attention. Compared to conventional devices, power density and energy conversion efficiency increase dramatically due to space constraints and electrostatic interactions at the nanoscale. Lamellar nanostructures, which can be easily fabricated by stacking two-dimensional nanosheets, may be a...
Wettability Alteration and its Effect on Oil Recovery by using Colloidal Nano-Silica in Oil Reservoirs
, M.Sc. Thesis Sharif University of Technology ; Ayatollahi, Shahabodin (Supervisor) ; Goodarznia, Iraj (Supervisor) ; Badakhshan, Amir (Co-Supervisor)
Abstract
As many oil fields are reaching their final stage of production, new technologies are required in order to maintain production and increase recovery of hydrocarbons. Among these techniques of enhanced oil recovery (EOR), chemical injection method focuses on increasing the effectiveness of waterflooding. Due to the relatively high costs and considerable adsorption on the rock formations, this method is no longer used. In Recent years nanofluids (nanoparticles dispersed in brine) have been used as a cheap, efficient and environmentally friendly alternative more than any other chemicals. It has been stated that the Smart Water method and enhanced oil recovery by SiO2 nanoparticles are effective...
Experimental Study of Internal Forced Convection of Ferrofluid Flow in Porous Media
, M.Sc. Thesis Sharif University of Technology ; Sadrhosseini, Hani (Supervisor) ; Shafii, Mohammad Behshad (Co-Advisor)
Abstract
The present work illustrates the results of an experimental study of ferrofluid flow in a tube subjected to a constant heat flux on its wall and filled with permeable material under the effect of magnetic field. The aim of this project is investigating the enhancement of heat transfer and obtaining a uniform temperature distribution inside the pipe. In order to achieve this, a porous medium with a porosity of 0.39 and ferrofluid with volume fractions of 0.6, 1.0 and 1.5 are used simultaneously, in the presence of magnetic field. The experiments are held for four different Reynolds numbers of 147.1, 167.3, 184.3 and 205.1. Also, four various modes of the oscillatory magnetic field are applied...
Mixed Convection of Nanofluids in Channels Partially Filled with a Porous Medium
, Ph.D. Dissertation Sharif University of Technology ; Molaei Dehkordi, Asghar (Supervisor)
Abstract
In the present study, mixed-convective heat transfer of nanofluids in a vertical rectangular channel partially filled with open-cell metal foam has been investigated experimentally and numerically. Al2O3–H2O nanofluids with different concentrations were synthesized and their stability was inspected with UV-Vis spectroscopy. The outlet temperature and pressure drop were measured for different nanofluid flow rates (i.e., Reynolds number values). In the numerical section, a two-dimensional volume-averaged form of the governing equations was used. The velocity and temperature profiles were obtained using finite difference method. The Brinkman–Forchheimer extended Darcy model and the...
Modeling of Flow of Nano-filled Viscoelastic Fluids and its Application in Rheometry
, M.Sc. Thesis Sharif University of Technology ; Ramazani Saadatabadi, Ahmad (Supervisor)
Abstract
Despite of passing many years from invention of Computational Fluid Dynamics (CFD), simulation of the fluid-solid interfaces and free surfaces are still completely challenging and progressive problems. In addition knowing and understanding nanotechnology huge applications,modeling of nano-fluids have been became a priority for researchers. Adding importance of Non-Newtonian fluids (especially polymeric solutions) to this two subjects, triangle topics of this research becomes vivid. In this research tried to consider and examine behavior of Newtonian,Generalized-Newtonian, Viscoelastic and nano-filled viscoelastic fluids in one and two phase mediums. we followed mesh free methods which are...
Effect of tiO_2 Nanoparticles on Heat and Drag Properties of Dilute Polymer Solutions
, M.Sc. Thesis Sharif University of Technology ; Ramezani Saadat Abadi, Ahmad (Supervisor) ; Mohammadi, Mohammad Reza ($item.subfieldsMap.e)
Abstract
In the present work, the experiments were carried out for two types of PAM (3330 and 3630) with three distinct concentrations (25, 40 and 55 ppm) and TiO_2-water nanofluid for four concentrations (1.5, 2, 2.5 and 3 vol. %), and the Nusselt number and friction factor for each of them expressed separately. The Reynolds number was in the range from 11000 to 21000. The steady state turbulent convective heat transfer and friction factor of the combination of TiO_2-water nanofluid and polymer 3330 in the coiled tube were investigated. The effects of the Reynolds number for 2 vol. % nanoparticles which consists of 25 ppm PAM (3330) determined at the constant temperature of 24°C. It was observed...
Characterization of magnetized CNT-based hybrid nanofluid subjected to convective phenomenon
, Article International Journal of Modern Physics B ; Volume 35, Issue 28 , 2021 ; 02179792 (ISSN) ; Khan, W. A ; Aqsa ; Waqas, M ; Abbas, S. Z ; Malik, M. Y ; Alqahtani, A. S ; Sharif University of Technology
World Scientific
2021
Abstract
Hybrid nanofluid gains attention of scientists due to its dynamic properties in various fields, and thus, hybrid nanofluids can be taken as an innovative form of nanofluids. Even though analysts acquire tremendous results in the field of hybrid nanofluids but yet no study has been carried out to predict magnetohydrodynamic effects in such fluid models. In this present analysis, influence of MHD has been investigated for the micro hybrid nanofluid over a stretched surface under convective conditions. Combine boundary layer equations for the flow have been altered into a suitable form via boundary layer approximations. Further, complete nonlinear system of equations has been numerically solved...
Investigation of the combination of TiO2 nanoparticles and drag reducer polymer effects on the heat transfer and drag characteristics of nanofluids
, Article Canadian Journal of Chemical Engineering ; Volume 96, Issue 6 , 2018 , Pages 1430-1440 ; 00084034 (ISSN) ; Ramazani Ahmad, S. A ; Sharif University of Technology
Wiley-Liss Inc
2018
Abstract
To compensate for drag increment due to the addition of nanoparticles to heat-transfer fluids, it seems that one could add drag reducer polymeric agents to these fluids. So, in this work, experiments were carried out for solutions of two types of polyacrylamide (FLOPAAM 3330S and FLOPAAM 3630S) at three distinct concentrations (25, 40, and 55 ppm), and TiO2-water nanofluid at concentrations of 0.015, 0.02, 0.025, and 0.03 L/L. The steady state turbulent convective heat transfer and the friction factor of the suspension of TiO2 in a dilute solution of very high molecular weight, polyacrylamide (hybrid fluid), in a coiled tube were analyzed. Experimental measurements were carried out from a...
The effect of nanoparticles on the mass transfer in Liquid–Liquid extraction
, Article Chemical Engineering Communications ; Volume 202, Issue 5 , Sep , 2015 , Pages 600-605 ; 00986445 (ISSN) ; Heydari Nasab, A ; Bastani, D ; Seife Kordi, A. A ; Sharif University of Technology
Taylor and Francis Ltd
2015
Abstract
This article investigates the effect of nanoparticles on mass transfer in the liquid–liquid extraction for the chemical system of n-butanol–succinic acid–water. For this purpose, nanofluids containing various concentrations of ZnO, carbon nanotubes (CNT), and TiO2 nanoparticles in water, as base fluid, were prepared. To examine the flow mode effect on mass transfer rate, different fluid modes including dropping and jetting were employed in the process. Results show that mass transfer rate enhancement depends on the kinds and the concentration of nanoparticles and the modes of flow. It was observed that after adding nanoparticles, the mass transfer rate significantly increases up to two-fold...
A numerical investigation on natural convection heat transfer in annular-finned concentric horizontal annulus using nanofluids: a parametric study
, Article Heat Transfer Engineering ; 2020 ; Zarei, M. M ; Hakkaki Fard, A ; Sharif University of Technology
Taylor and Francis Ltd
2020
Abstract
Natural convection heat transfer in a concentric horizontal annulus with annular fins is numerically studied. Due to the low thermal conductivity of water, CuO-water and Al2O3-water nanofluids were used as heat transfer fluids. The effect of three different parameters, including fin spacing, fin eccentricity, and fin thickness at different fin diameters and Rayleigh number range of 104 to 9 (Formula presented.) 105, were studied. The obtained results revealed that Al2O3-water nanofluid has the highest heat transfer rate. The calculated heat transfer rates for Al2O3-water nanofluid for Rayleigh numbers of 9 (Formula presented.) 105, 105, and 104 were respectively up to 12.1%, 26.2%, and 31.6%...
A numerical investigation on natural convection heat transfer in annular-finned concentric horizontal annulus using nanofluids: a parametric study
, Article Heat Transfer Engineering ; Volume 42, Issue 22 , 2021 , Pages 1926-1948 ; 01457632 (ISSN) ; Zarei, M. M ; Hakkaki Fard, A ; Sharif University of Technology
Taylor and Francis Ltd
2021
Abstract
Natural convection heat transfer in a concentric horizontal annulus with annular fins is numerically studied. Due to the low thermal conductivity of water, CuO-water and Al2O3-water nanofluids were used as heat transfer fluids. The effect of three different parameters, including fin spacing, fin eccentricity, and fin thickness at different fin diameters and Rayleigh number range of 104 to 9 (Formula presented.) 105, were studied. The obtained results revealed that Al2O3-water nanofluid has the highest heat transfer rate. The calculated heat transfer rates for Al2O3-water nanofluid for Rayleigh numbers of 9 (Formula presented.) 105, 105, and 104 were respectively up to 12.1%, 26.2%, and 31.6%...
Optimisation of combined cooling, heating and power (CCHP) systems incorporating the solar and geothermal energy: a review study
, Article International Journal of Ambient Energy ; Volume 43, Issue 1 , 2022 , Pages 42-60 ; 01430750 (ISSN) ; Assareh, E ; Moltames, R ; Olazar, M ; Nedaei, M ; Parvaz, F ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
Recently, numerous studies have focused on simulation and optimisation of combined cooling, heat, and power (CCHP) systems. This research, from a different perspective, aims to conduct a comprehensive review of the studies performed in the field of solar, geothermal or combined sources, and subsequently analysing the multi-objective evolutionary algorithms to identify the most efficient situation, which satisfy researchers' needs in order to attain a better performance in their ongoing or future research projects. It is worth noting that multi-objective optimisation in these cycles is based on optimising a thermodynamic term (exergy efficiency, thermal efficiency, etc.) and an economic term...
Nanofluid-assisted gas to hydrate (GTH) energy conversion for promoting CO 2 recovery and sequestration processes in the petroleum industry
, Article Petroleum Science and Technology ; Volume 34, Issue 1 , 2016 , Pages 37-43 ; 10916466 (ISSN) ; Montazeri, V ; Sharif University of Technology
Taylor and Francis Inc
2016
Abstract
In this work the enhancement of gas to hydrate conversion employing the nanographene oxide (NGO)-based nanofluid regarding CO2 capture and sequestration recovery is investigated. A new series of experiments are carried out at different pressures, temperatures, agitation intensities and NGO promoter concentrations by using a newly developed fully automated GTH (gas to hydrate) energy converter. According to the presented results at the 3 MPa and 275.15 K and in the presence of 30 ppm NGO, it is possible to reach a CO2 gas to hydrate conversion of 95% at a low impeller speed in less than 2.5 h, which is quite interesting from an energy consumption standpoint. The presented approach can have...
The effect of nanoparticles on spontaneous imbibition of brine into initially oil-wet sandstones
, Article Energy Sources, Part A: Recovery, Utilization and Environmental Effects ; Volume 41, Issue 22 , 2019 , Pages 2746-2756 ; 15567036 (ISSN) ; Ghasemi Dehkordi, M ; Sharif University of Technology
Taylor and Francis Inc
2019
Abstract
In this paper, the effect of silica nanoparticles on oil production due to the spontaneous imbibition of brine into oil-wet sandstones has been studied. The imbibed fluids were NaCl 3 wt. % solutions containing various concentrations of nanoparticles and the recovered oil for each solution was compared. The results revealed that nanoparticles yielded more oil recovery. Nanofluid was used after brine imbibition, and the oil recovery increased from 17.8% to 40% while in the case of using the same nanofluid as the first imbibed fluid the oil recovery was 53%. Also, the results indicated that the oil recovery depends on nanoparticle concentrations. © 2019, © 2019 Taylor & Francis Group, LLC
The stability and surface activity of environmentally responsive surface-modified silica nanoparticles: the importance of hydrophobicity
, Article Journal of Dispersion Science and Technology ; Volume 41, Issue 9 , 2020 , Pages 1299-1310 ; Mohammadi, A ; Sharif University of Technology
Taylor and Francis Inc
2020
Abstract
In this study, the effect of hydrophobicity of environmentally responsive surface-modified silica nanoparticles on the stability and surface activity of the nanoparticles is examined. To this end, n-propyl, n-hexyl, or n-octyl chains and methoxy poly(ethylene glycol) chains at various quantities were coated covalently on the surface of silica nanoparticles to regulate the hydrophobicity of the responsive nanoparticles. Various experimental tools such as stability analysis, interfacial-tension and contact-angle measurements, and emulsion formation were performed to investigate the effect of hydrophobicity. It became evident that the presence of the hydrophobic agents influences considerably...
The impacts of silica nanoparticles coupled with low-salinity water on wettability and interfacial tension: Experiments on a carbonate core
, Article Journal of Dispersion Science and Technology ; Volume 41, Issue 8 , 2020 , Pages 1159-1173 ; Jamialahmadi, M ; Esmaeilzadeh, F ; Wood, D. A ; Ghazanfari, M. H ; Sharif University of Technology
Taylor and Francis Inc
2020
Abstract
Two main reservoir mechanisms that impact oil recovery factors are wettability alteration and interfacial tension (IFT) change. In this study, these two key mechanisms are evaluated experimentally for samples from the Asmari (carbonate) oil reservoir utilizing silica nanoparticles in the presence of low-salinity water. The nanofluid, rock formation and crude oil samples were prepared meticulously to ensure meaningful experimental could be conducted over a range of low-salinity conditions. The results show that across the range of salinities studied, the absolute value of zeta potential of nanofluids decreases with increasing total dissolved solids (TDS) in the water treated with silica...
A novel correlation approach for viscosity prediction of water based nanofluids of Al2O3, TiO2, SiO2 and CuO
, Article Journal of the Taiwan Institute of Chemical Engineers ; Volume 58 , 2016 , Pages 19-27 ; 18761070 (ISSN) ; Daryasafar, A ; MoradiKoochi, M ; Moghadasi, J ; BabaeiMeybodi, R ; KhorramGhahfarokhi, A ; Sharif University of Technology
Taiwan Institute of Chemical Engineers
2016
Abstract
Nanofluids viscosity is one of the most important thermophysical properties in nanofluids usage especially in chemical and petroleum engineering applications. So it is highly desirable to predict the viscosity of nanofluids accurately. Experimental measurements are impossible in most situations and present models are not comprehensive and efficient especially for high temperature, high volume concentration and high viscosity values. In this study, a new correlation has been developed based on the comprehensive database of water based Al2O3, TiO2, SiO2 and CuO nanofluids viscosity data found in literature. The proposed correlation uses temperature, nanoparticle size, nanoparticle volumetric...
Effect of temperature and concentration on thermal conductivity and viscosity of ferrofluid loaded with carbon nanotubes
, Article Heat and Mass Transfer/Waerme- und Stoffuebertragung ; 2015 , Pages 1-9 ; 09477411 (ISSN) ; Saghafian, M ; Salimpour, M. R ; Shafii, M. B ; Sharif University of Technology
Springer Verlag
2015
Abstract
The aim of this paper is to investigate the thermal conductivity and viscosity of a hybrid nanofluid containing tetramethylammonium hydroxide (TMAH) coated Fe3O4 nanoparticles and gum arabic (GA) coated carbon nanotubes (CNTs), experimentally. The magnetic nanoparticles and CNTs are physically attached as the result of interaction between the TMAH and GA molecules. The morphology and structure of the samples are characterized with X-ray diffraction (XRD) and transmission electron microscopy (TEM). The experiments are carried out in the magnetic nanoparticles volume concentration range of 0.1–0.9 %, CNT volume concentration range of 0.05–1.35 % and the temperature range of 25–55 °C. The...
Effect of temperature and concentration on thermal conductivity and viscosity of ferrofluid loaded with carbon nanotubes
, Article Heat and Mass Transfer/Waerme- und Stoffuebertragung ; Volume 52, Issue 10 , 2016 , Pages 2293-2301 ; 09477411 (ISSN) ; Saghafian, M ; Salimpour, M. R ; Shafii, M. B ; Sharif University of Technology
Springer Verlag
2016
Abstract
The aim of this paper is to investigate the thermal conductivity and viscosity of a hybrid nanofluid containing tetramethylammonium hydroxide (TMAH) coated Fe3O4 nanoparticles and gum arabic (GA) coated carbon nanotubes (CNTs), experimentally. The magnetic nanoparticles and CNTs are physically attached as the result of interaction between the TMAH and GA molecules. The morphology and structure of the samples are characterized with X-ray diffraction (XRD) and transmission electron microscopy (TEM). The experiments are carried out in the magnetic nanoparticles volume concentration range of 0.1–0.9 %, CNT volume concentration range of 0.05–1.35 % and the temperature range of 25–55 °C. The...