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kazemzadeh--ezatollah
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MultiScale Pore Network Modeling to be Compared with Experimental Results
, M.Sc. Thesis Sharif University of Technology ; Ayatollahi, Shahab (Supervisor) ; Jamshidi, Saeed (Supervisor) ; Kazemzadeh, Ezatollah (Supervisor)
Abstract
The study of porous media, especially in pore-scales (micro and nano scales), is of particular importance in various sciences such as petroleum engineering, chemical, and civil engineering. Determine the physics of the pore scale to understand it better, identify the conditions for it to enforce the laws better, and explain some of the phenomena unknown so far, and finally obtain the parameters performed in the laboratory for specific samples are the main goals of these studies. One of the most well-known methods for analyzing porous media is pore network modeling. These models are always affected by the macroscopic structure of porous media, such as their multiscale state. In this study, an...
Incompressible stokes flow calculation using a finite point method
, Article Scientia Iranica ; Volume 10, Issue 1 , 2003 , Pages 44-55 ; 10263098 (ISSN) ; Parsinejad, F ; Sharif University of Technology
Sharif University of Technology
2003
Abstract
In this paper, a finite point method is employed to solve the incompressible laminar Stokes flow. A moving least-squares approximation, using linear and quadratic basis functions, in conjunction with a point collocation method, has been utilized to discretize the governing equations. Two examples, including the driven cavity and the fully developed channel flow, are solved showing the accuracy and applicability of the method. In summary, the solutions for the linear basis case exhibit a large sensitivity to the size of the domain of influence of the weighting function, in contrast to the quadratic basis case
Experimental and Numerical Investigation of Engine Performance Parameters with Spark Timing Alteration to Minimize the Vibration (Knock Index).
,
M.Sc. Thesis
Sharif University of Technology
;
Kazemzadeh Hannani, Siamak
(Supervisor)
Abstract
In this thesis, engine performance parameters such as power, torque, fuel consumption and in-cylinder pressure are investigated with considering ignition timing in order to achieve the minimum value of knock index. The implemented methods include engine dynamometer tests and simulating vehicle powertrain in GT- POWER software. Based on the acceptable precision of the GT-POWER model, it can be used to predict the engine performance in other ignition timings. Final results prove that for wide open throttle status altering the ignition timing to reach the minimum possible value impact differently on the engine performance so that in low engine speeds for basic and new ignition timings, a...
A novel method for producing unequal sized droplets in micro- and nanofluidic channels
, Article European Physical Journal E ; Volume 38, Issue 9 , September , 2015 ; 12928941 (ISSN) ; Moosavi, A ; Kazemzadeh Hannani, S ; Sharif University of Technology
Springer New York LLC
2015
Abstract
Abstract: We propose a novel method for producing unequal sized droplets through breakup of droplets. This method does not have the disadvantages of the available methods and also reduces the dependence of the droplets volume ratio on the inlet velocity of the system by up to 26 percent. The employed method for investigating the proposed system relies on 3D numerical simulation using the VOF algorithm and the results have been obtained with various valve ratios for both the micro- and nanoscale. The results indicate that the droplet length during the breakup process increases linearly with time. The droplet length at the nanoscale is smaller than that at the micro scale. It has been shown...
Exergy analysis of parabolic trough solar collectors using Al2O3/synthetic oil nanofluid
, Article Solar Energy ; Volume 173 , 2018 , Pages 1236-1247 ; 0038092X (ISSN) ; Shamloo, A ; Kazemzadeh Hannani, S ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
Parabolic trough solar collector (PTC) is one of the most mature and widely used type of solar energy harnessing devices. Therefore, investigation of the effect of various operational conditions on the overall efficiency of these devices has been topic of substantial interest in the recent decade. Moreover, utilization of nanoparticles as a useful additive to the working fluid should be examined thoroughly to optimize the collector's outputs. To do so, in the present study, energy and exergy efficiencies of a typical PTC as a function of several involving parameters are numerically calculated. These parameters are nanoparticle volume fraction (from 0 to 5 percent), environment wind speed...
Molecular dynamics study of friction reduction of two-phase flows on surfaces using 3d hierarchical nanostructures
, Article Journal of Physical Chemistry C ; 2019 ; 19327447 (ISSN) ; Moosavi, A ; Kazemzadeh Hannani, S ; Sharif University of Technology
American Chemical Society
2019
Abstract
The use of superhydrophobic surfaces is one the most promising methods for reducing the friction and increasing the flow rate in fluid transfer systems. Because in such systems the surface structure plays a key role, in this study, we explore the performance of the hierarchical nanostructures. These nanostructures are inspired by the superhydrophobic surface of the lotus leaf. We consider a flow between two walls with hierarchical nanostructures and simulate the system via the molecular dynamics method. The size of the nanostructures and the distance between them have been studied to find whether a design with a maximum flow rate exists. The nanostructures have two parts, a bigger part on...
Simulation of water purification using magnetically ultra-responsive micro- and nanoscavengers
, Article Journal of Water Process Engineering ; Volume 24 , 2018 , Pages 63-73 ; 22147144 (ISSN) ; Moosavi, A ; Kazemzadeh Hannani, S ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
Access to clean water is one of the challenges of the 21st century. Thus water purification is inevitable. One method of water treatment is purification by magnetic particles in the presence of magnetic field. The contaminants are attached to the magnetic particles and then by applying a magnetic field, magnetic particles and, thus, the pollutants can be collected. For the optimal design of a water treatment system, the effect of important parameters in the design, such as magnetic fields, particle size, and Reynolds number are determined numerically by modeling and simulating the water treatment process. Two methods are used to create the magnetic field: permanent magnet and coils. It is...
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
Abstract
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...
Energy, exergy, exergoeconomic, and economic analysis of a novel power generation cycle integrated with seawater desalination system using the cold energy of liquified natural gas
, Article Energy Conversion and Management ; Volume 243 , 2021 ; 01968904 (ISSN) ; Afshin, H ; Kazemzadeh Hannani, S ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Utilizing the cold energy of liquefied natural gas can reduce the demand of burning fossil fuels for work production and employing refrigeration cycles for seawater desalination. A novel low-temperature cascade power generation cycle combined with a seawater freeze desalination system is proposed to retrieve the cold energy from liquified natural gas. Binary working fluids are utilized to decrease the irreversibilities of the power cycle and enhance the energy recovery efficiency. The effects of the important temperatures of the cycle, pinch temperature of the heat exchangers, number of turbines and their efficiency on the cycle performance are investigated. Optimization of the work...
Heat transfer intensification of turbulent forced convection by inserting discontinuous twisted tapes in a wavy tube; hydrothermal and thermodynamics analysis
, Article Chemical Engineering and Processing - Process Intensification ; Volume 181 , 2022 ; 02552701 (ISSN) ; Sadrhosseini, H ; Kazemzadeh Hannani, S ; Sharif University of Technology
Elsevier B.V
2022
Abstract
The current study presents a numerical investigation on turbulent hydrothermal characteristics in a wavy passage equipped with discontinuous twisted tapes. The working fluid is water and passage walls are kept under constant wall temperature. The effect of Reynolds number (Re = 2500, 4500, 6500, 8500 and 10500), twist angle (TA = 90∘ and 180∘) and inclination angle (IA = 15∘ and 30∘) on velocity fields and streamlines, temperature contours, Nusselt number, friction factor, turbulent kinetic energy (TKE), thermal performance factor (TPF), energy efficiency factor (EEF) and entropy generation rate are evaluated. More uniform temperature and velocity fields can be found as both wavy passage and...
Manufacturing Constant Volume Combustion Chamber and Simulation and Analysis of the Flame front Development
, M.Sc. Thesis Sharif University of Technology ; Kazemzadeh Hannani, Siamak (Supervisor)
Abstract
The application of internal combustion engine is vast in different context, such as transportation and power generation. Therefore to investigation of these objects and the importance of flame front development, a combustion chamber with constant volume is designed and manufactured. The chamber designing is based on the experimental knowledge and numerical simulation of chamber and glasses. The combustion chamber made of stainless steel and contained transparent quartz glasses in both side of it to provide the ability of using schlieren photography method and investigation of flame. The great advantage of present chamber is the capability of different type of combustion, including fuel and...
Numerical Study of Oxygen Enrichment on NO Pollution Spread in an Ignition Chamber
, M.Sc. Thesis Sharif University of Technology ; Kazemzadeh Hannani, Siamak (Supervisor)
Abstract
In the present study, a 3D combustion chamber was simulated using FLUENT6.32. The objectives were to obtain detailed information on the combustion characteristics and NO formation in the furnace, and also to examine the effect of Oxygen enrichment on the combustion process. The combustion chamber has internal dimensions of 60 cm wide, 90 cm high and 190 cm long. The fuel pipe diameter is 1.25 cm and the air pipe diameter is 3.5 cm. The 3-D Reynolds Averaged Navier Stokes (RANS) equations together with standard k-ε turbulence model are solved by Fluent 6.3. Air/fuel flow rate ratio is varied as 1.3, 3.2 and 5.1 and the oxygen enriched flow rates are 28, 54, 68 lit/min. NO emission was...
Wind Farm Layout Optimization
, M.Sc. Thesis Sharif University of Technology ; Kazemzadeh Hannani, Siamak (Supervisor)
Abstract
In this work, wind farm layout optimization problem is dealt with a new approach. The aim of this work is maximizing the output power of a wind farm by considering wake loses. Layout optimization minimizes the wake loses regarding the wind direction. Three different wind scenarios including different wind direction angles, wind direction blowing probabilities and Weibull distribution parameters for wind speed are assumed. Since, the problem is nonlinear and constrained, imperialist competitive algorithm is used as a modern and powerful algorithm for continuous optimization problems. The optimization outcomes indicate that imperialist competitive algorithm yields promising results....
Simulating Different Energy Optimization Solutions in Buildings and Providing a Set of the Best Approaches with the Aim of Optimizing Energy and Simultaneously Providing Comfort In Different Climates of Iran
, M.Sc. Thesis Sharif University of Technology ; Kazemzadeh Hannani, Siamak (Supervisor)
Abstract
Sustainable development is a general concept in all aspects of human life, including social, economic, environmental, etc. Since one of the pillars of achieving sustainable development is the optimization of energy consumption, and on the other hand, energy consumption in buildings accounts for one third of the country's annual energy consumption, so it is very important to provide solutions that can reduce energy consumption in this sector. Therefore, in this research, with the aim of optimizing energy consumption in buildings, examples in different climates of Iran are selected and effective strategies to reduce energy consumption are identified according to each climate and used to...
Second law based modeling to optimum design of high capacity pulse tube refrigerators
, Article International Journal of Refrigeration ; Volume 32, Issue 1 , 2009 , Pages 58-69 ; 01407007 (ISSN) ; Saidi, M. H ; Kazemzadeh Hannani, S ; Sharif University of Technology
2009
Abstract
The optimum design of a high capacity double inlet pulse tube refrigerator based on second law of thermodynamics has been presented in this paper. Second law is applied to calculate the work loss in the regenerator and to optimize the cryocooler performance. To investigate the behavior of the pulse tube refrigerator, mass and energy balance equations are applied to several control volumes of the cryocooler cycle. A complete system of conservation equations is employed to solve the regenerator analytically. The proposed model reports the cooling capacity of 110 W at 80 K cold end temperature at frequency of 50 Hz, orifice conductance of 0.4 and double inlet coefficient of 0.6, with 2.4 kW net...
A finite-volume ELLAM for non-linear flux convection-diffusion problems
, Article International Journal of Non-Linear Mechanics ; Volume 44, Issue 2 , 2009 , Pages 129-136 ; 00207462 (ISSN) ; Taghizadeh Manzari, M ; Kazemzadeh Hannani, S ; Sharif University of Technology
2009
Abstract
In this paper, a modified finite-volume Eulerian-Lagrangian localized adjoint method (FVELLAM) extended for convection-diffusion problems with a non-linear flux function is introduced. Tracking schemes are discussed using viscous Burgers' equation. It is shown that in order to have smooth results, only the new time level values should be used in tracking process. Then, the proposed method is employed to study immiscible incompressible two-phase flows in porous media. Various one- and two-dimensional test cases involving internal sources and sinks are solved and accuracy of solution and performance of the method are investigated by comparing the results obtained using FVELLAM with those of...
Parametric study of droplet formation and characteristics within microfluidic devices - A case study
, Article International Journal of Applied Mechanics ; Volume 12, Issue 7 , 2020 ; Shamloo, A ; Kazemzadeh Hannani, S ; Sharif University of Technology
World Scientific
2020
Abstract
Droplet-based microfluidics technologies hold great attention in a wide range of applications, including chemical analysis, drug screening, and food industries. This work aimed to describe the effects of different physical properties of the two immiscible phases on droplet formation in a flow-focusing microfluidic device and determining proper flow rates to form a droplet within the desired size range. A numerical model was developed to solve the governing equations of two-phase flow and the results were validated with previous experimental results. The results demonstrate different types of droplet formation regimes from dripping to jetting and different production rates of droplets as a...
Thermal transport in combined pressure - Electroosmotically driven flow in microchannels
, Article 10th Intersociety Conference on Thermal and Thermomechanical Phenomena and Emerging Technologies in Electronic Systems, ITherm 2006, San Diego, CA, 30 May 2006 through 2 June 2006 ; Volume 2006 , 2006 , Pages 63-70 ; 0780395247 (ISBN); 9780780395244 (ISBN) ; Taghizadeh Manzari, M ; Kazemzadeh Hannani, S ; Sharif University of Technology
2006
Abstract
An analytical solution is presented to study the heat transfer characteristics of the combined pressure - electroosmotically driven flow in planar microchannels. The physical model includes the Joule heating effect to predict the convective heat transfer coefficient in two dimensional microchannels. The velocity field, which is a function of external electrical field, electroosmotic mobility, fluid viscosity and the pressure gradient, is obtained by solving the hydrodynamically fully-developed laminar Navier-Stokes equations considering the electrokinetic body force for low wall zeta potentials. Then, assuming a thermally fully-developed flow, the temperature distribution and the Nusselt...
Machine learning approach for carrier surface design in carrier-based dry powder inhalation
, Article Computers and Chemical Engineering ; Volume 151 , 2021 ; 00981354 (ISSN) ; Alishiri, M ; Lau, R ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
In this study, a machine learning approach was applied to evaluate the impact of operating and design variables on dry powder inhalation efficiency. Emitted dose and fine particle fraction data were extracted from the literature for a variety of drug and carrier combinations. Carrier surface properties are obtained by image analysis of SEM images reported. Models combining artificial neural network and genetic algorithm were developed to determine the emitted dose and fine particle fraction. Design strategies for the carrier surface were also proposed to enhance the fine particle fractions. © 2021 Elsevier Ltd
Application and performance comparison of high-resolution central schemes for the black oil model
, Article International Journal of Numerical Methods for Heat and Fluid Flow ; Volume 17, Issue 7 , 2007 , Pages 736-753 ; 09615539 (ISSN) ; Taghizadeh Manzari, M ; Kazemzadeh Hannani, S ; Sharif University of Technology
2007
Abstract
Purpose - The purpose of this paper is to investigate the performance of a specific class of high-resolution central schemes in conjunction with the black oil models for hydrocarbon reservoir simulation. Design/methodology/approach - A generalized black oil model is adopted, in which the solubility of gas in both oil and water and evaporation of oil are considered, leading to a system of equations prone to degeneracy. A computer code is generated and three test cases are solved to evaluate the performance of various schemes in terms of accuracy and discontinuity handling. Findings - It is shown that, although some of the central schemes are highly sensitive to the choice of...