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Hydrograph attenuation along a pipe using a Flush tank
, Article Urban Water Management: Challenges and Oppurtunities - 11th International Conference on Computing and Control for the Water Industry ; Volume 1 , 2011 ; 0953914089 (ISBN); 9780953914081 (ISBN) ; Mahmoud Borghei, S ; Sharif University of Technology
Abstract
One of the miscellaneous units that are frequently used in water and wastewater systems is flush tank. Flush tank increases the self cleaning velocity in the conduit, and helps to clear the conduits from deposits and contaminations. While these units have been used for many years, there is not enough information about the hydraulic performance of these units in respect to the discharge, distance from the tank and the pipe hydraulics. In this paper the experimental results from observed hydrographs at different distances from the flush tank in a pipe has been presented. The variables include; volume of releasing water (or inlet hydrograph), upstream head, pipe diameter (3 cm), pipe length and...
Biofiltration of hexane vapor: Experimental and neural model analysis
, Article Clean - Soil, Air, Water ; Volume 39, Issue 9 , 2011 , Pages 813-819 ; 18630650 (ISSN) ; Halladj, R ; Saber, M ; Ferdowsi, M ; Nasernejad, B ; Sharif University of Technology
Abstract
Biofiltration is a commonlypracticed biological technique to remove volatile compounds from waste gas streams. From an industrial view-point, biofilter (BF) operation should be flexible to handle temperatures and inlet load (IL) variations. A compost BF was operated at different temperatures (30-45°C) and at various inlet loading rates (ILR; 8-598gm -3h -1) under intermittent loading conditions. Complete removal of n-hexane was observed at 30 and 35°C at ILRs up to 330gm -3h -1. Besides, 20-75% of the pollutant was removed at 40°C, corresponding to the different ILs applied to the BF. Increasing the temperature to 45°C decreased the removal efficiency (RE) significantly. A feed forward...
Experimental investigation of a novel passive solar still with additional condensation on sidewalls
, Article Desalination and Water Treatment ; Volume 89 , 2017 , Pages 29-35 ; 19443994 (ISSN) ; Favakeh, A ; Faegh, M ; Sadrhosseini, H ; Sharif University of Technology
Abstract
In common solar stills, a portion of the produced vapor undesirably condenses on the sidewalls and runs down to be mixed with saline water in the basin. This results in lower distillate output of the system. The aim of this study was to improve the condensation process of a solar still without complicating its structure to collect the water condensed on sidewalls. The proposed solar still was made of two containers nested one inside the other such that the smaller container, containing saline water, fitted easily into the larger container. There was a thin gap between the two in which condensed liquid on sidewalls, ran down and was collected from the bottom of the larger container. The...
Evaluation of flapping wing propulsion based on a new experimentally validated aeroelastic model
, Article Scientia Iranica ; Volume 19, Issue 3 , 2012 , Pages 472-482 ; 10263098 (ISSN) ; Aliabadi, S. K ; Sharif University of Technology
2012
Abstract
To evaluate the propulsion system capabilities of a Flapping Micro Air Vehicle (FMAV), a new aeroelastic model of a typical flexible FMAV is developed, utilizing the Euler-Bernoulli torsion beam and quasi steady aerodynamic model. The new model accounts for all existing complex interactions between the mass, inertia, elastic properties, aerodynamic loading, flapping amplitude and frequency of the FMAV, as well as the effects of several geometric and design parameters. To validate the proposed theoretical model, a typical FMAV, as well as an instrumented test stand for the online measurement of forces, flapping angle and power consumption, has been constructed. The experimental results are...
Experimental Study of the Wing Sweep Angle Effect on the Pressure Distribution of a Half Model
, M.Sc. Thesis Sharif University of Technology ; Soltani, Mohammad Reza (Supervisor)
Abstract
In this thesis the behavior of a 3D wing has investigated by Flow visualization and pressure acquisition test. The goal of this tests was considering changes in 3D wing section parameter in comparison with 2D airfoils. The performed Tests showed that variation in 3D wing treatment is affected by finite aspect ratio and sweep angle and also indicate changes in pressure profile, increasing pressure peak and decreasing effective speed. CFD studies has conducted to investigate special effect of sweep angle and show that lift and drag coefficient decrease with increasing sweep angle. Also different section pressure profile near the wing tip and intersection of wing/fuselage varies and miss...
Design and Fabrication Bi-fuel Gas Turbine Combustion Chamber Basis of Turbocharger
, M.Sc. Thesis Sharif University of Technology ; Farshchi, Mohammad (Supervisor) ; Hajilouy Benisi, Ali (Co-Advisor)
Abstract
This research is done as a continuation of previous efforts to develop a turbojet engine from a turbocharger at departments of mechanical and aerospace engineering of Sharif University of Technology and describes the necessary steps in order to design and build a dual fuel combustion chamber for a small, turbocharger based turbojet engine. At first, zero-dimensional analysis is done using a code written in Matlab. Using this code, matching of the compressor and turbine in the turbojet thermodynamic cycle is verified and the operating line of the turbojet engine has been extracted. Henceforth, operating conditions of the combustion chamber to start design process is determined. In designing...
An Experimental and Numerical Study on Jet Electrohydrodynamics
, Ph.D. Dissertation Sharif University of Technology ; Morad, Mohammad Reza (Supervisor)
Abstract
Liquid jet behavior in an intense electric field is studied experimentally and numerically.Imaging is used in experiments to charactrize jet behavior. Electrospray of ethanol using a simple needle in a wide range of operating conditions is investigated. Liquid meniscus is captured using a high-speed camera and different electrospray modes are described based on involved forces. A new nozzle is invented that broadens the stability margins of the useful cone-jet mode. The physical mechanisms of the new cone-jet is discussed and it is characterized using appropriate dimensionless parameters. A simple jet in presence of a gaseous crossflow and a normal electric field is also studied. The liquid...
Experimental Aerodynamic Modeling of a Rigid Flapping Wing
, M.Sc. Thesis Sharif University of Technology ; Pourtakdoust, Hossein (Supervisor)
Abstract
Flapping Aerial Vehicles (FAVs) are those kinds of aerial vehicles in which the wings are responsible for simultaneous producing of lift and thrust forces. To provide necessary aerodynamic loads, flapping wings employ various unsteady mechanisms. They often fly at relatively high Angle of Attacks (AoA), respective to the relative flow. The aerodynamic modelling of flapping wing has always been a challenging task. The unspecified assumptions in the existing models, make them almost insufficient in flight simulation applications. Therefore, this paper aims to develop a generalized aerodynamic model. To this aim, a comprehensive investigation has been conducted on some of previous aerodynamic...
Bi-amino surface functionalized nanoparticles: Synthesis and binary system dye removal from wastewater containing anionic dyes
, Article Desalination and Water Treatment ; Volume 70 , 2017 , Pages 347-354 ; 19443994 (ISSN) ; Ghezelbash, M ; Ghotbei, C ; Kazemeini, M ; Sharif University of Technology
Desalination Publications
2017
Abstract
In this paper, copper oxide nanoparticle was synthesized, and its surface was modified using N-(2-aminoethyl)-3-(trimethoxysilyl)propylamine. The bi-amino surface functionalized nanoparticle (BASFN) was used to remove anionic dyes from single and binary systems. The scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, energy-dispersive X-ray spectroscopy (EDAX) and X-ray diffraction were used to characterize the nanoparticle. Direct Red 80 (DR80) and Direct Green 6 (DG6) were used as anionic dyes. The effect of adsorbent dosage, dye concentration and pH on dye removal was evaluated. Kinetic of dye adsorption on BASFN followed pseudo-second order. The results...
Experimental modeling of twin-entry radial turbine
, Article Iranian Journal of Science and Technology, Transaction B: Engineering ; Volume 32, Issue 6 , December , 2008 , Pages 571-584 ; 10286284 (ISSN) ; Hajilouy Benisi, A ; Sharif University of Technology
2008
Abstract
In this paper the performance characteristics of a turbocharger twin-entry radial inflow gas turbine with asymmetrical volute and rotor tip diameter of 73.6 mm in steady state and under full and partial admission conditions are investigated. The employed method is based on one dimensional performance prediction which is developed for partial admission conditions. Furthermore, this method is developed for the asymmetrical volute of the turbine considering the flow specifications. Experimental investigation of the research was carried out on special test facilities under full and partial admission conditions for a wide range of speeds. A comparison of experimental and modeling results shows...
Jet impact geometry and plunge pool dimensions effects on dynamic pressures at pool sidewalls
, Article Canadian Journal of Civil Engineering ; Volume 35, Issue 4 , 2008 , Pages 408-417 ; 03151468 (ISSN) ; Zarnani, P ; Sharif University of Technology
2008
Abstract
A plunge pool is one of the energy dissipater structures for high head dams, which ensures stability of the dam under extreme hydrodynamic pressure, due to falling jet impacts. The excess energy of the jet is dissipated, together with significant impact pressure exerted on the floor and pool walls. Thus, appropriate assessment of jet dynamic characteristics in the plunge pool is essential. This research presents experimental results focusing on. the distribution of mean and extreme pressure fluctuations on the sidewalls, due to circular and rectangular plunging jets, and the effects of pool dimension, especially in narrow valleys. The experimental variables are discharge, geometry of jet,...
Experimental Study of Transient Two-Phase Slug Flow (Air-Water)
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mahmoud (Supervisor)
Abstract
Fluid transient in a conduit is an unsteady flow, which is followed by the change in the flow rate condition. Pressure transients in pipeline systems are caused by fluid flow interruption from operational changes such as starting/stopping of pumps, sudden changes to valve setting, etc. Fluid transient analysis is commonly based on the assumption of no air in the liquid. However, air entrainment, trapped air pockets, free gas, and dissolved gases frequently are present in the pipeline. In fact, Air changes flow properties and transient pressure peaks in comparison with single-phase flow. Experimental study has been carried out to verify characteristics of transient pressure inside a...
Experimental and Simulation Study of Water Alternating Hydrocarbon - CO2 Mixture Gas in one of Iranian Oil Reservoirs
, M.Sc. Thesis Sharif University of Technology ; Taghikhani, Vahid (Supervisor) ; Ghazanfari, Mohammad Hossein (Supervisor) ; Badakhshan, Amir (Supervisor)
Abstract
In this work the effect of composition changes of the injection gas (Hydrocarbon gas + carbon dioxide) on Water Alternating Gas (WAG) performance in immiscible flooding which has been rarely attended in the available literature is investigated. Core flood experiments are conducted on a 10 cm length Sarvak sandstone core sample at 46 degree C and at immiscible condition, i.e., below the minimum miscible pressure (MMP) of the oil sample using pure CO2 as injected Gas.The influence of injection WAG ratio on oil recovery also is investigated. Artificial injection brine which is made by dissolving NaCl into distilled water with 5000 ppm (mg/L), NaftShahr oil which has about 41 API gravity and...
Experimental and Modeling Study of Controlled Salinity Water Injection for Enhanced Oil Recovery from one of Iranial Oil Reservoirs
, M.Sc. Thesis Sharif University of Technology ; Ghazanfari, Mohammad Hossein (Supervisor) ; Masihi, Mohsen (Co-Advisor)
Abstract
From previous years, water injection was considered as one of the most common methods for enhanced oil recovery. But recently much attention has been paid on the use of low salinity water (LSW) as an enhanced oil recovery fluid. The main mechanism that causes improve oil recovery is wettability alteration to a more water wet state. The change observed in recovery factor during LSW flooding induced from changes in relative permeability and capillary pressure when different levels of salinity are used. However, a few researchers tried to evaluate how macroscopic flow functions depend on the salinity of injected water. To this end, a series oil displacements by water performed on sandstone rock...
Experimental Study of Formation Damage Reduction during Drilling of Horizontal Wells Using Nanoparticles
, M.Sc. Thesis Sharif University of Technology ; Ghazanfari, Mohammad Hossein (Supervisor)
Abstract
One the basic challenges during drilling of both vertical and horizontal wellbores is due to mud filtrate invasion into the formation. Addition of nanoparticles to composition of drilling fluid has been recognized as a measure of control and reduction of filtrate invasion. Despite notable advances in formulation of nano-enhanced drilling fluids, effects of surface wettability of nanoparticles on their performance have not been studied with any precision. Moreover, return permeability of a grain packed porous media after extreme invasion by mud filtrate has not been experimentally measured in a radial system, yet. The last but not least, Generation and development of mud cake opposite the...
Experimental Study and Modeling of Scale up in Multi-blocks Fractured Porous Media
, M.Sc. Thesis Sharif University of Technology ; Ghazanfari, Mohammad Hossein (Supervisor) ; Rostami, Behzad (Supervisor)
Abstract
Fractured reservoirs constitute a major portion of world’s petroleum reservoirs. Gravity drainage is the controlling production mechanism in these reservoirs. Thus, investigation of performance and oil production in fractured models has been the subject of many researches. Despite the considerable number of experimental and modeling studies in this area, the method of scale-up in single or multi block models is not broadly investigated. This work is divided into two experimental and modeling sections. For the experimental study, free fall gravity drainage experiments in synthetic single or multi block porous media were performed in order to investigate effects of different parameters...
Experimental Study on Increasing the Electrical Efficiency of Photovoltaic Panel with Decreasing Rear Surface Temperature
, M.Sc. Thesis Sharif University of Technology ; Moosavi, Ali (Supervisor) ; Shafiee, Afshin (Co-Advisor)
Abstract
Hybrid photovoltaic thermal system (PV/T) is a pioneer mechanical and electrical system which can produce both thermal and electrical energy for domestic or industrial purposes. As the solar cell’s material is semiconductor, the electrical output of them reversely modifies with the reduction of solar cell’s operating temperature. One of the most operational and cost-effective methods that has been investigated is active cooling. The photovoltaic panel cools down with a channel under the PV’s rear surface and a fan in the channel outlet. The producing heat can warm up cold water of a house or a factory. In addition to active cooling, it is smart to utilize passive cooling such as artificial...
Experimental Investigation of Streaming in a Thermoacoustic Engine
, M.Sc. Thesis Sharif University of Technology ; Ghorbanian, Kaveh (Supervisor)
Abstract
Streaming is a phenomenon that is driven by acoustic oscillations and leads to the reduction of efficiency in thermoacoustic engines. Acoustic streaming induced by acoustic oscillations is a steady mass-flux of second order and can cause heat leak that greatly reduces efficiency. There are two types of streaming in thermoacoustic engines; Gedeon streaming and Rayleigh streaming. Gedeon streaming exists within the porous media and Rayleigh streaming occurs in the thermal buffer tube. Thermal buffer tube separates the hot heat exchanger from secondary cold heat exchanger. In this thesis, experimental study of Gedeon streaming and Rayleigh streaming has been accomplished by temperature...
Experimental Investigation of Surfactant Flooding for EOR in Layered Heavy Oil Reservoirs using Micromodel Apparatus
, M.Sc. Thesis Sharif University of Technology ; Rashtchian, Davood (Supervisor) ; Massihi, Mohsen (Supervisor) ; Ghazanfari, Mohammad Hossein (Supervisor)
Abstract
Nowadays, due to limitation of production from conventional oil reservoirs, enhanced recovery from heavy oil reservoirs are of great concern. In heavy oil reservoirs, only 5% of initial oil in place (IOIP) is producible due to high viscosity. Water flooding increases oil recovery just up to 10% which is due to improper mobility ratio. One of popular methods for increasing oil recovery is injection of chemical materials. Chemical methods are used in reservoirs that have high degree of heterogeneity like heterogeneous and layered reservoirs. These heterogeneities cause diversion and loss of injected water which leads to remaining of oil in its place. Using surface active agents, as a popular...
Experimental Investigation of Geometric Parameters Effect on Energy Harvesting from FIV in Bluff Bodies
, M.Sc. Thesis Sharif University of Technology ; Ebrahimi, Abbas (Supervisor)
Abstract
The purpose of this research is to design and construct a test stand for the study of the kinematic and flow pattern of bluff bodies oscillating motion due to the induction of wake vortices. An experimental investigation was conducted to explore the effect of bluff bodies cross section to optimize the amount of electrical energy withdraw by electromagnetic harvester. The tests are carried out on cylinders with square section and rectangular sections with a length to width ratio of 1/2 and 2/1 and height of 50 cm, at speeds of 5 to 35 m/s in eiffel type wind tunnel. The effect of cylinder cross-section on the amount of energy harvested showed that the amplitude of oscillation in square-shaped...