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porous-materials
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Analytical Solution to Partial Differential Equations Derived from Thermo-Hydro-Mechanical Analysis
, M.Sc. Thesis Sharif University of Technology ; Pak, Ali (Supervisor)
Abstract
In this research an analytical and semi analytical solution to the differential eqautions derived from coupled analysis of heat transfer, moisture transfer and solid deformation in porous materials is presented. In first section, differential equations derived from Hydro-mechanical analysis of an unsaturated soil layer with limited thickness was considered and it is assumed that pore air pressure is equal to atmospheric pressure. To solve the system of equations laplace transform is used.In second section, the effect of daily changes in temperature on transient heat and moisture transfer in semi infinite layer is studied in three dimension. Energy conservation equation and pore liquid mass...
Experimental Investigation of Heat Transfer Coefficient of Porous Materials in Various Air Pressures
, M.Sc. Thesis Sharif University of Technology ; Nouri Broujerdi, Ali (Supervisor)
Abstract
Heat transfer in porous media has recently become an important subject in mechanical engineering. Heat transfer in porous media is central in many applications involving industrial devices (chemical engineering, heat exchangers, nuclear reactor, etc...) as well as complex geological formations (in situ combustion and pyrolysis, geothermal sites, etc...). On track to achieve heat transfer methods and heat transfer coefficients of porous materials, this investigation describes the design process of fabrication and experimental analysis of calculation the conduction heat transfer coefficient of the uniform porous materials. We report on thermal conductivity measurements performed on uniform...
Hierarchical Multi-scale Analysis using Nonlinear Finite Element & its Application to Porous Media
, M.Sc. Thesis Sharif University of Technology ; Naghdabadi, Reza (Supervisor) ; Sohrabpour, Saeed (Supervisor)
Abstract
Porous materials, with diverse applications in engineering branches, are categorized as multi-scale. A multi-scale material is one which shows different structure and/or behavior in two or more different length scales. There are physical models which can calculate the macroscopic properties of such materials by using both the properties and volume fractions of the ingredients. However, the number of such theories which can handle problems in the fields of elasticity and hydrodynamics is much less; the fields in which the tensor orders of the properties are more than one. Fortunately, in recent years, a new method named "Computational Multi-scale Homogenization" has been offered to homogenize...
Numerical Study of the Effect of Permeability in Single-Phase Flow in Porous Media
, M.Sc. Thesis Sharif University of Technology ; Sadrhosseini, Hani (Supervisor) ; Ashjari, Mohammad Ali (Supervisor)
Abstract
Present study is to simulate laminar flow in a channel exposed to heat flux from the walls and filled with porous media by software ANSYS CFX in finite volume method. The analysis is based on the Naviere-Stokes equations in the flow field which are modified to Brinkman-Forchheimer equations to be applicable for porous media. Effect of Reynolds number and permeability on seepage velocity, temperature distribution, heat transfer and pressure drop are investigated.Simulations are performed for two cases: fully developed flow at the entrance of the porous media and developing flow, which are corresponding to the Reynolds numbers of Re=77.6 and Re=1553 respectively (U= 0.01 m/s and U= 0.2 m/s)....
Ti-rich TiO2 tubular nanolettuces by electrochemical anodization for all-solid-state high-rate supercapacitor devices
, Article ChemSusChem ; Volume 12, Issue 17 , 2019 , Pages 4064-4073 ; 18645631 (ISSN) ; Khajehdehi, O ; Sabbah, A ; Naseri, N ; Sharif University of Technology
Wiley-VCH Verlag
2019
Abstract
Supercapacitors store charge by ion adsorption or fast redox reactions on the surface of porous materials. One of the bottlenecks in this field is the development of biocompatible and high-rate supercapacitor devices by scalable fabrication processes. Herein, a Ti-rich anatase TiO2 material that addresses the above-mentioned challenges is reported. Tubular nanolettuces were fabricated by a cost-effective and fast anodization process of Ti foil. They attained a large potential window of 2.5 V in a neutral electrolyte owing to the high activation energy for water splitting of the (1 0 1) facet. Aqueous and all-solid-state devices showed diffusion time constants of 46 and 1700 ms, as well as...
Free fall and controlled gravity drainage processes in fractured porous media: Laboratory and modelling investigation
, Article Canadian Journal of Chemical Engineering ; Volume 93, Issue 12 , October , 2015 , Pages 2286-2297 ; 00084034 (ISSN) ; Ayatollahi, S ; Masihi, M ; Sharif University of Technology
Wiley-Liss Inc
2015
Abstract
Gravity drainage is known to be one of the most effective methods for oil recovery in fractured reservoirs. In this study, both free fall and controlled gravity drainage processes were studied using a transparent fractured experimental model, followed by modelling using commercial CFD software. The governing equations were employed based on the Darcy and mass conservation laws and partial pressure formulation. Comprehensive examination was done on variables such as fluid saturation, velocity, and pressure distribution in the matrix and fracture, as well as fluid front level and production rate. Additionally, effects of the model parameters on the gravity drainage performance were...
Heavy oil recovery using ASP flooding: A pore-level experimental study in fractured five-spot micromodels
, Article Canadian Journal of Chemical Engineering ; Volume 94, Issue 4 , 2016 , Pages 779-791 ; 00084034 (ISSN) ; Mohammadzadeh, O ; Kord, S ; Chatzis, I ; Sharif University of Technology
Wiley-Liss Inc
2016
Abstract
Although alkaline-surfactant-polymer (ASP) flooding has proven efficient for heavy oil recovery, the displacement mechanisms and efficiency of this process should be discussed further in fractured porous media. In this study, several ASP flooding tests were conducted in fractured glass-etched micromodels with a typical waterflood geometrical configuration, i.e. five-spot injection-production pattern. The ASP flooding tests were conducted at constant injection flow rates but different fracture geometrical characteristics. The ASP solutions consisted of five polymers, two surfactants, and three alkaline types. It was found that using synthetic polymers, especially hydrolyzed polyacrylamide...
Numerical investigation of two phase flow in micromodel porous media: effects of wettability, heterogeneity, and viscosity
, Article Canadian Journal of Chemical Engineering ; Volume 95, Issue 6 , 2017 , Pages 1213-1223 ; 00084034 (ISSN) ; Rokhforouz, M. R ; Ayatollahi, S ; Sharif University of Technology
Wiley-Liss Inc
2017
Abstract
The aim of the present work is to assess the effects of wettability, heterogeneity, and viscosity differences on water-oil displacement process in micromodel porous media through numerical modelling. The two-phase flow was simulated by Cahn-Hilliard phase field method (PFM) using a finite element package. The micromodel was initially saturated with oil (wetting phase) and oil was produced through invasion of the displacing phase into the matrix. The computed oil and water saturations were in good agreement with those obtained by the visual flooding experiment. Using the validated model, sensitivity analysis was performed to investigate the effects of different wettability states,...
Experimental investigation of dynamic asphaltene adsorption on calcite packs: The impact of single and mixed-salt brine films
, Article Canadian Journal of Chemical Engineering ; Volume 97, Issue 7 , 2019 , Pages 2028-2038 ; 00084034 (ISSN) ; Ghotbi, C ; Jafari Behbahani, T ; Bakhshi, P ; Sharif University of Technology
Wiley-Liss Inc
2019
Abstract
In this study, the dynamic adsorption of asphaltene on a calcite surface is investigated. This study investigates the effect of mixed-salt brines on asphaltene adsorption. The results of this work can facilitate the understanding of the complex wettability behaviour of carbonate reservoirs. All experiments were performed in porous media, which were sand-packs filled with calcite powder, to study the influence of the type and concentration of salt on adsorption. The experiments were conducted with asphaltene concentration of 500 mg/L for brines of NaCl, Na2SO4, and a mixture of the two at various ionic strengths. In addition, two tests were performed with an asphaltene concentration of 2000...
A priori error estimation of upscaled coarse grids for water-flooding process
, Article Canadian Journal of Chemical Engineering ; Volume 94, Issue 8 , 2016 , Pages 1612-1626 ; 00084034 (ISSN) ; Firoozabadi, B ; Sharif University of Technology
Wiley-Liss Inc
Abstract
Advanced reservoir characterization methods can yield geological models at a very fine resolution, containing 1011–1018 cells, while the common reservoir simulators can only handle much lower numbers of cells due to computer hardware limitations. The process of coarsening a fine-scale model to a simulation model is known as upscaling. Predicting the accuracy of simulation results over an upscaled grid with respect to the fine grid is highly important, as it can yield the optimum upscaling process. In this paper, permeability-based and velocity-based a priori error estimation techniques are proposed by introducing image processing-based comparison methods in the context of upscaling. The...
Modeling of semi-solid A356 alloy under upsetting process
, Article 9th International Conference on Semi-Solid Processing of Alloys and Composites, S2P 2006, Busan, 11 September 2006 through 13 September 2006 ; Volume 116-117 , 2006 , Pages 622-625 ; 10120394 (ISSN); 3908451264 (ISBN); 9783908451266 (ISBN) ; Aashuri, H ; Sharif University of Technology
Trans Tech Publications Ltd
2006
Abstract
The flow behavior of a semi-solid A356 alloy at high solid fraction was studied. The mushy zone was considered as an effective two-phase, so that the solid continuum can be compressible porous media, and the liquid phase interaction with the solid skeleton was of Darcy type. The semi-solid flow through the upsetting test was modeled in ABAQUS finite element method software. The Gurson yield criterion has been developed for the modeling process of the flow behavior of solid porous medium. Specimens were globulized by a thermomechanical process and then were tested for various percentages of upsetting. The distribution of solid fraction along the radius of the specimens at different height...
Modeling of semi-solid A356 alloy under upsetting process
, Article Solid State Phenomena ; Volume 116-117 , 2006 , Pages 622-625 ; 10120394 (ISSN) ; Aashuri, H ; Sharif University of Technology
Trans Tech Publications Ltd
2006
Abstract
The flow behavior of a semi-solid A356 alloy at high solid fraction was studied. The mushy zone was considered as an effective two-phase, so that the solid continuum can be compressible porous media, and the liquid phase interaction with the solid skeleton was of Darcy type. The semi-solid flow through the upsetting test was modeled in ABAQUS finite element method software. The Gurson yield criterion has been developed for the modeling process of the flow behavior of solid porous medium. Specimens were globulized by a thermomechanical process and then were tested for various percentages of upsetting. The distribution of solid fraction along the radius of the specimens at different height...
Polyethylene glycol-coated porous magnetic nanoparticles for targeted delivery of chemotherapeutics under magnetic hyperthermia condition
, Article International Journal of Hyperthermia ; 2018 ; 02656736 (ISSN) ; Hedayatnasab, Z ; Karimian, H ; Sarraf, M ; Yeong, C. H ; Madaah Hosseini, H. R ; Abu Kasim, N. H ; Wong, T. W ; Rahman, N. A ; Sharif University of Technology
Taylor and Francis Ltd
2018
Abstract
Purpose: Although magnetite nanoparticles (MNPs) are promising agents for hyperthermia therapy, insufficient drug encapsulation efficacies inhibit their application as nanocarriers in the targeted drug delivery systems. In this study, porous magnetite nanoparticles (PMNPs) were synthesized and coated with a thermosensitive polymeric shell to obtain a synergistic effect of hyperthermia and chemotherapy. Materials and methods: PMNPs were produced using cetyltrimethyl ammonium bromide template and then coated by a polyethylene glycol layer with molecular weight of 1500 Da (PEG1500) and phase transition temperature of 48 ± 2 °C to endow a thermosensitive behavior. The profile of drug release...
A hybrid assimilation scheme for characterization of three-phase flow in porous media
, Article Inverse Problems in Science and Engineering ; Volume 27, Issue 9 , 2019 , Pages 1195-1220 ; 17415977 (ISSN) ; Pishvaie, M. R ; Bozorgmehry Boozarjomehry, R ; Sharif University of Technology
Taylor and Francis Ltd
2019
Abstract
In this study, ensemble Kalman filter (EnKF) is first applied to estimate absolute and relative permeabilities jointly under three-phase flow condition in the porous media. By assimilating historical data, absolute permeability field is adjusted progressively towards its reference. However, assimilation process does not improve the estimation of all relative permeability parameters, and some of them are poorly estimated at the end of assimilation. To improve the estimation of the relative permeability curves, we propose a new hybrid approach in which the estimation process of the absolute and relative permeabilities is separated. In this approach, gridblock permeabilities are again estimated...
Thermal and hydraulic performance of rectangular microchannel heat sinks with trapezoidal porous configuration
, Article Numerical Heat Transfer; Part A: Applications ; Volume 81, Issue 3-6 , 2022 , Pages 72-93 ; 10407782 (ISSN) ; Vafai, K ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
In this article, the thermal and hydraulic capacity of a rectangular microchannel heat sink with different trapezoidal porous configuration’s inlet heights (Formula presented.) and outlet heights (Formula presented.) are examined. A three-dimensional model is used for microchannels with miscellaneous trapezoidal porous configuration’s inlet and outlet heights, and the laminar fluid flow and conjugate heat transfer equations are numerically solved. Darcy-Brinkmen-Forchheimer equation is utilized for transport through the porous region. For microchannels with miscellaneous porous distribution’s inlet and outlet heights, the Nusselt number, pressure drop and figure of merit (FOM), a criterion...
Effect of magnetic field on internal forced convection of ferrofluid flow in porous media
, Article Experimental Heat Transfer ; Volume 29, Issue 1 , 2016 , Pages 1-16 ; 08916152 (ISSN) ; Sehat, A ; Shafii, M. B ; Sharif University of Technology
Taylor and Francis Ltd
Abstract
Enhancement of heat transfer is investigated in an experimental study of ferrofluid flow in a tube subjected to a constant and uniform heat flux on its wall, filled with permeable material under the effect of magnetic field. Effect of ferrofluid volume fraction, Reynolds number, and different frequencies of various magnetic field modes on heat transfer is examined by measuring the temperature on the wall. Using ferrofluid under the effect of magnetic field improves the heat transfer, and porous media makes the temperature distribution more uniform. Volumetric percentage of nano-particles has the greatest effect on the heat transfer
Effect of nanoparticle behaviour on mud cake buildup for directional and horizontal wells: mathematical modelling and experimental study
, Article Journal of Experimental Nanoscience ; Volume 11, Issue 12 , 2016 , Pages 975-999 ; 17458080 (ISSN) ; Ghazanfari, M. H ; Shahbazi, K ; Zargar, G ; Sharif University of Technology
Taylor and Francis Ltd
Abstract
The present study examined the effect of nanoparticle size and geometry on filter cake buildup during dynamic filtration using experimental and modeling approaches. A dynamic filtration setup was proposed and designed to test cross-flow circulation against a synthetic core at a constant differential pressure. The proposed mathematical model considers the critical deposition boundary of the porous media for particles along with drag, lift, friction, buoyancy, permeate, and electrostatic forces. The comprehensive model response allowed investigation of the aggregation and shape of nanoparticles at different cross-flow inclinations. The drag and lift force coefficients and moment of inertia of...
The effect of brine salinity on water-in-oil emulsion stability through droplet size distribution analysis: a case study
, Article Journal of Dispersion Science and Technology ; Volume 39, Issue 5 , 2018 , Pages 721-733 ; 01932691 (ISSN) ; Ayatollahi, S ; Sharif University of Technology
Taylor and Francis Inc
2018
Abstract
Water-in-oil emulsion usually forms during waterflooding in some heavy oil reservoirs. The composition and salinity of the injected water critically affect the w/o emulsion droplet size distribution, which control the emulsion stability and emulsion flow in porous media. The aim of the present work is to assess the effect of different sea water salinities on w/o emulsion stability through microscopic imaging. Therefore, w/o emulsions were prepared with different sea water samples, which were synthesized to resemble Persian Gulf, Mediterranean, Red Sea, and North Sea water samples. The results showed that log-normal distribution function predicts very well the experimental data to track the...
Physicomechanical Properties of Porous Materials by Spark Plasma Sintering
, Article Critical Reviews in Solid State and Materials Sciences ; Volume 45, Issue 1 , 2020 , Pages 22-65 ; Azarniya, A ; Safavi, M. S ; Farshbaf Ahmadipour, M ; Esmaeeli Seraji, M ; Sovizi, S ; Saqaei, M ; Yamanoglu, R ; Soltaninejad, M ; Madaah Hosseini, H. R ; Ramakrishna, S ; Kawasaki, A ; Adams, S ; Reddy, M. V ; Sharif University of Technology
Taylor and Francis Inc
2020
Abstract
Metallic or ceramic micro/nanoporous materials have attracted particular attention due to some interesting structural and functional properties. There exist a variety of methods for producing porous materials by which optimized features can be reached. Spark plasma sintering (SPS) is one of these new-emerging approaches. This technique is often combined with conventional technologies and produce a variety of porous structures with tailorable microstructure and physicomechanical properties. This review addresses SPS and obtainable porous materials with nanoscale and microscale microstructural features. The processing methods, microstructural phenomena, and physicomechanical properties of...
Darcy model for the study of the fluid flow and heat transfer around a cylinder embedded in porous media
, Article International Journal for Computational Methods in Engineering Science and Mechanics ; Volume 7, Issue 5 , 2006 , Pages 323-329 ; 15502287 (ISSN) ; Nouri Borujerdi, A ; Sharif University of Technology
Taylor and Francis Inc
2006
Abstract
Steady-state convective heat transfer around a circular cylinder embedded in porous media is studied in the range of low and moderate Peclet numbers less than 40. The cylinder is at constant temperature and the Darcy model is used for the analysis of fluid flow and heat transfer in porous media. The governing equations are discretised using finite volume approach based on staggered grids. The powerlaw scheme is used in the numerical solution and a SIMPLE-like algorithm is developed and used in the solution process. It is found that the numerical algorithm is sufficiently efficient in the range of Peclet numbers less than 40. Parametric studies are done for better understanding of the porous...