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ultrasonics
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Design and Fabrication of Ultrasonic Level-meter System
, M.Sc. Thesis Sharif University of Technology ; Nejat Pishkenari, Hossein (Supervisor) ; Salarieh, Hassan (Co-Supervisor)
Abstract
In many industries, including oil and gas industries, power plants, refineries, petrochemicals, steel and cement industries, industrial complexes and consumer industries, there are tanks for storing materials. It is necessary to measure level of products while they are stored in tanks of different sizes. Ultrasonic is one of the non-contact and accurate measurement technologies that can provide a suitable solution for liquid tank monitoring. The purpose of this thesis is to design and build the electronic parts (transmitter and receiver circuits) of an ultrasonic system that is capable of detecting levels at a distance of less than 5 meters with an accuracy of 0.5 % full scale. In this...
Investigating the role of ultrasonic wave on two-phase relative permeability in a free gravity drainage process
, Article Scientia Iranica ; Vol. 21, issue. 3 , 2014 , p. 763-771 ; Karimi, R ; Najafi, I ; Ghazanfari, M. H ; Ghotbi, C ; Sharif University of Technology
Abstract
In this work, the process of free gravity drainage under the influence of ultrasonic waves was investigated. A glass bead pack porous medium was used to perform free fall gravity drainage experiments. The tests were performed in the presence and absence of ultrasonic waves, and the data of recovery were recorded versus time under both conditions. The wetting phase relative permeability curves were obtained using the data of recovery versus time, based on the Hagoort backward methodology. Subsequently, using the wetting phase relative permeability curve, the relative permeability of non-wetting phases were calculated by performing history matching to the experimental production data. The...
Ultrasonic assisted deep drilling of Inconel 738LC superalloy
, Article Procedia CIRP, Leuven ; Volume 6 , April , 2013 , Pages 571-576 ; 22128271 (ISSN) ; Mehbudi, P ; Akbari, J ; Sohrabi, M ; Sharif University of Technology
2013
Abstract
Superalloys have a poor machinability and are often drilled using Electro Discharge Machining (EDM) methods. However EDM is a time-consuming process and has low surface integrity. Ultrasonic Assisted Drilling (UAD) technology is a modern method of drilling such materials. Although this method has very high capabilities, it has not been introduced widely to industry. In this study a special horn is designed and used to apply both rotation and vibration to drill bits. It can transfer power with high efficiency and has the capability to change tools easily. The setup is used to conduct deep drilling tests on Inconel 738LC with depth-to-diameter ratio of 10. The effect of ultrasonic vibration...
Finding tuning frequency for symmetric and anti-symmetric lamb waves using FEM
, Article Export | Download | More... 28th Congress of the International Council of the Aeronautical Sciences 2012, ICAS 2012 ; Volume 3 , 2012 , Pages 2412-2416 ; 9781622767540 (ISBN) ; Moosavi, M. R ; Abedian, A ; Golzad, I ; Sharif University of Technology
2012
Abstract
In the area of life assessment, none-destructive methods of inspection and evaluation (NDI/NDE) play important role to ensure if astructure is still healthy enough to get used of. Using ultrasonic stress waves is one of the easiest and cheapest methods of NDI. Accordingly, different modes of lamb wave are mostly of interest..There are various methods for generating lamb waves. One of these methods is using piezoelectric wafer actuator/sensors (PWAS). Accordingly, one of the most important parts of this method is to generate right mode via an appropriate choose of actuating frequency. In this text using a new method for finding tuning frequencies of different lamb wave modes proposed. For...
Taguchi's optimization in ultrasonic drilling of alumina ceramic
, Article Proceedings of the 6th International Conference on Leading Edge Manufacturing in 21st Century, LEM 2011, 8 November 2011 through 10 November 2011 ; November , 2011 ; Akbari, J ; Japan Society of Mechanical Engineers (JSME),; Manufacturing and Machine Tool Division ; Sharif University of Technology
2011
Abstract
This paper outlines the effectiveness of the ultrasonic machining of alumina in terms of tool wear rate of the tool used and the material removal rate of work piece produced. The optimum combination of various input factors as type of abrasive slurry, their size and concentration, power and feed rate, in the machining of alumina has been determined by applying the Taguchi technique, also analysis is used to choose the best shape for horn. The study shows that among input parameters, power has the highest effect on MRR (material removal rate). Effects of grit size and feed rate on TWR (tool wear rate) also investigated
Study the influence of ultrasonic vibration on grinding of Ti6Al4V
, Article Proceedings of the 6th International Conference on Leading Edge Manufacturing in 21st Century, LEM 2011, 8 November 2011 through 10 November 2011 ; Novembe , 2011 ; Movahhedy, M. R ; Akbari, J ; Sharif University of Technology
2011
Abstract
Titanium alloys, in particular Ti6Al4V, are increasingly used recently due to high strength-to-weight ratio, biocompatibility and robust mechanical-properties at high temperatures. However, Ti6Al4V have poor machinability because of their poor thermal conductivity and high reactivity. Usually in conventional grinding (CG) of these alloys, surface burning is unavoidable. Ultrasonic assisted grinding (UAG) is an efficient method for overcoming the poor machinability of such materials. In this research, effect of imposed vibration on grinding of Ti6Al4V is studied. Obtained results show forces and surface roughness are reduced 18% and 12% by UAG comparing to CG respectively. It also results in...
Energy aspects and workpiece surface characteristics in ultrasonic-assisted cylindrical grinding of alumina-zirconia ceramics
, Article International Journal of Machine Tools and Manufacture ; Volume 90 , 2015 , Pages 16-28 ; 08906955 (ISSN) ; Tawakoli, T ; Akbari, J ; Sharif University of Technology
Abstract
Ultrasonic assisted grinding is a novel method for improving the grinding process of difficult-to-cut materials. In the present research a novel setup has been designed and manufactured for utilizing ultrasonic vibrations in external cylindrical grinding. The designed ultrasonic head vibrates a rotating workpiece in axial direction. An alumina-zirconia ceramic (AZ90) has been selected as the workpiece material. Energy aspects and workpiece surface characteristics of ultrasonic assisted cylindrical grinding (UACG) and conventional cylindrical grinding (CG) processes have been analytically modeled and corresponding grinding experiments have been performed. The combined kinematics of the...
Modeling and optimization of an elliptical shape ultrasonic motor using combination of finite element method and design of experiments
, Article ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE), 12 November 2010 through 18 November 2010, Vancouver, BC ; Volume 8, Issue PARTS A AND B , 2010 , Pages 491-496 ; 9780791844458 (ISBN) ; Akbari, J ; Shahidi, A. R ; Darki, A. A ; Sharif University of Technology
2010
Abstract
Standing-wave ultrasonic motors are a modern class of positioning systems, which are used to deliver a high precision linear or rotary motion with an unlimited stroke. The design process should be performed through an effective optimization algorithm in order to guaranty proper and efficient function of these motors. An optimization method of ultrasonic motors is proposed based on the combination of finite element method and factorial design as a design of experiments in this study. The results show the ability of this method in optimal design of ultrasonic motors especially those which have a complex structure and multi modes operation principle
Quantitative analysis of ultrasonic wave radiation on reversibility and kinetics of asphaltene flocculation
, Article 4th International Conference and Exhibition: New Discoveries through Integration of Geosciences, Saint Petersburg, 5 April 2010 through 8 April 2010 ; 2010 ; Najafi, I ; Ghazanfari, M. H ; Kharrat, R ; Ghotbi, C ; Sharif University of Technology
European Association of Geoscientists and Engineers, EAGE
2010
Abstract
Recently, it was found that ultrasonic wave technology can be used as a method for asphaltene deposits removal from the near wellbore region. However, ultrasounds can affect asphaltene resolution.In this work, asphaltene resolution in several crude oil samples exposed to ultrasonic waves for different time intervals is studied by confocal microscopy. The colloidal structure of flocks is described by analysis of asphaltene particle size distribution to investigate ultrasonic application in solving asphaltene deposition problems.. The results show that for the first 90 minutes of flocculation time, the size of aggregates increases rapidly, and reaction limited aggregation model matches well...
Modeling and simulation of oil well stimulation by high power ultrasonic irradiation
, Article Acta Acustica united with Acustica ; Volume 103, Issue 3 , 2017 , Pages 411-420 ; 16101928 (ISSN) ; Ahmad Ramazani, S. A ; Jamshidi, S ; Moghaddam, A. K ; Sharif University of Technology
S. Hirzel Verlag GmbH
2017
Abstract
Ultrasonic waves have been extensively used in many industrial applications including clean devices, pipes and vessels. A clear extension of this usage is the removal of wellbore contaminants by exposing it to high-power ultrasonic waves. In this paper, a mathematical model for ultrasonic propagation through the porous medium around the wellbore is presented. The equations of wave propagation are written in a cylindrical coordinate according to Biot theory and the induced stress in the rock are calculated at each point using finite difference approach Comparison of imposed local stresses with adhesion forces between scales and rock, the properties of ultrasonic transducer, such as frequency...
Design and analysis of an elliptical-shaped linear ultrasonic motor
, Article Sensors and Actuators, A: Physical ; Volume 278 , 2018 , Pages 67-77 ; 09244247 (ISSN) ; Akbari, J ; Sharif University of Technology
Elsevier B.V
2018
Abstract
A linear ultrasonic motor (LUSM) with an elliptical-shaped metallic stator and two orthogonal vibration modes is presented in this research. The driving tip's desired vibration is generated by the excitation of two piezoelectric actuators installed inside the stator by two sinusoidal voltages with ±[Formula presented] phase difference. The working principle of the motor is described and mathematically formulated. Furthermore, finite element analysis and parametric optimization are performed to finalize the motor design. A prototype of the motor is fabricated and evaluated by identification and operation tests. The experimental and numerical characteristic curves of the motor are presented...
Laboratory and in situ investigation of the compressive strength of CFRD concrete
, Article Construction and Building Materials ; Volume 242 , 2020 ; Nazari, R ; Houshmand Khaneghahi, M ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
One of the most essential and costly stages in Concrete Face Rockfill Dams (CFRD) construction is to implement the concrete at the upstream face of the dam without joints. As the face concrete is considered as the most integral part to prevent water penetration in CFRDs, it's quality control is of paramount importance. One of the conventional approaches for quality control of the concrete which is used in CFRD is the compressive strength of laboratory samples. The comparison of laboratory and in situ measurements provides information about the accuracy of the obtained results. This research investigates the correlation of concrete compressive strength determined by using different methods in...
Blind angle and angular range detection in planar and limited-view geometries for photoacoustic tomography
, Article 29th Iranian Conference on Electrical Engineering, ICEE 2021, 18 May 2021 through 20 May 2021 ; 2021 , Pages 922-926 ; 9781665433655 (ISBN) ; Kavehvash, Z ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
In this paper, the relationship between the position of ultrasound transducers from the photoacoustic source and the reconstructed image is investigated. Our studies have shown that the distance of the transducer and its location from the photoacoustic source specifically affects and is closely related to the quality of the reconstructed image of the source. Also, we introduce a concept called blind angle for photoacoustic computed tomography (PACT) that have planar or circular limited-view geometry. Complete and accurate equations of this relationship are presented in this paper for all different 2D photoacoustic geometries. The main source of these equations is the spherically of the...
Study of Ultrasonic Vibration Assisted Grinding of Fused Silica Ceramic
, M.Sc. Thesis Sharif University of Technology ; Movahhedy, Mohammad Reza (Supervisor) ; Akbari, Javad (Supervisor)
Abstract
Fused silica is an important industrial ceramics with low machinability due to high brittleness, low hardness and high chemical reactivity. Traditional machining of this ceramic is very inefficient. Ultrasonic vibrations assisted grinding of this ceramic could create pieces with high accuracy and good surface quality. The main objective of this thesis is to investigative Ultrasonic vibrations assisted grinding of fused silica. Ultrasonic vibrations with a frequency of 20 kHz and amplitude in the range of 10-40 micron is applied to workpiece during grinding process. It is shown that in the ultrasonic assisted grinding, machining forces decreases by up to 45% and surface roughness reduces by...
The Application of Ultrasonic Waves for Determining the Liquid Level in Reactor for Monitoring a Process Reactor
, M.Sc. Thesis Sharif University of Technology ; Hajsadeghi, Khosrow (Supervisor)
Abstract
In this research non-contact ultrasonic based method is used for liquid level measurement in a container. A system has been designed and developed to determine the liquid level and show the results on a personal computer. The system contains three main parts, which are mechanical and electronic parts and the programming. The setup can measure the liquid level with the accuracy of 1cm. An ATMEGA8 microprocessor commands to relays and controls the pumps. The pumps are used to change the height of the liquid in the containers to accurately calibrate the sensor and test its operation. The ultrasonic sensor, which is mounted above the vessel, transfers the data to an ATMEGA64 microprocessor for...
Structural Health Monitoring and Damage Detection of Pipelines
, M.Sc. Thesis Sharif University of Technology ; Haj Sadeghi, Khosro (Supervisor)
Abstract
Pipelines are the preferred means for transporting of liquid or gas phase materials. The economy of many countries is extremely dependent upon a large network of pipelines systems to transport and distribute the nation’s energy resources. Damages to the pipe structure may cause leakage and result in economic losses or even loss of life. Developing methods for detecting the anomalies and damages to the structure before they lead to catastrophic events is vital. Multiple pipeline misadventures over the past several years have resulted in hundreds of fatalities and billions of dollars in property damages. These accidents demonstrate that the current monitoring methods are not sufficient...
Modeling, Study of Operational Characteristics and Fabrication of an Ultrasonic Linear Motor
, Ph.D. Dissertation Sharif University of Technology ; Akbari, Javad (Supervisor)
Abstract
Nowadays, piezoelectric motors are used as one of the suitable options in the modern motion control field and precise positioning systems due to their suitable functional characteristics such as high power to weight ratio, fast dynamic response, direct drive motion, integrated structure without backlash and possibility of miniature design. Accordingly, the present dissertation is defined in order to develop a comprehensive path for modeling, analysis and optimization of the ultrasonic piezoelectric motors. In this study, the focus is on the ultrasonic motors with an elliptical structure, but the results can be used for other structures as well. In the present work, the process of modeling of...
Model study on the kinetics of scale removal due to ultrasonic radiation
, Article 73rd European Association of Geoscientists and Engineers Conference and Exhibition 2011: Unconventional Resources and the Role of Technology. Incorporating SPE EUROPEC 2011 ; Volume 7 , 2011 , Pages 5657-5659 ; 9781617829666 (ISBN) ; Hemmati, N ; Mashayekhi, L ; Sharif University of Technology
Abstract
Scale formation is one of the major problems in oilfields. Removal of scales is a difficult process due to their relative hardness and low solubility. Therefore it is valuable to find a method which can remove damages caused by scales. Ultrasonic radiation is known have the sufficient energy to remove the scales. Our purpose is to investigate the role of ultrasound on permeability increments due to scale removal. Some experiments were carried out to find these effects and observed that ultrasound has increased volumetric mass transfer, concentration and solubility limits. We also worked on a model presented by Tahmasebi et. al[2010] and applied changes on it to make it able to predict...
X-ray diffraction analysis and williamson-hall method in usdm model for estimating more accurate values of stress-strain of unit cell and super cells (2 × 2 × 2) of hydroxyapatite, confirmed by ultrasonic pulse-echo test
, Article Materials ; Volume 14, Issue 11 , 2021 ; 19961944 (ISSN) ; Palevicius, A ; Dashti, A ; Nasiri, S ; Monshi, A ; Doustmohammadi, A ; Vilkauskas, A ; Janusas, G ; Sharif University of Technology
MDPI AG
2021
Abstract
Taking into account X-ray diffraction, one of the well-known methods for calculating the stress-strain of crystals is Williamson-Hall (W–H). The W-H method has three models, namely (1) Uniform deformation model (UDM); (2) Uniform stress deformation model (USDM); and (3) Uniform deformation energy density model (UDEDM). The USDM and UDEDM models are directly related to the modulus of elasticity (E). Young’s modulus is a key parameter in engineering design and materials development. Young’s modulus is considered in USDM and UDEDM models, but in all previous studies, researchers used the average values of Young’s modulus or they calculated Young’s modulus only for a sharp peak of an XRD pattern...
The Effect of Electroporation on Ultrasund Signals
, M.Sc. Thesis Sharif University of Technology ; Zahedi, Edmond (Supervisor)
Abstract
In this thesis, a cellular model of electroporation process and its detection by ultrasound signals is proposed. Electroporation is permeabilization of the cell membrane, caused by an external electric field. The resulted pores open cell’s membrane to large or hydrophilic molecules. The process of Electroporation has been used in Gene therapy and treatment of solid tumors. In this project, first we made a phantom of electroporated tissue and a phantom of normal tissue and then we simulated their responses to a linear array ultrasound transducer. By comparision of received signals from phantoms the probable effect of electroporation on ultrasound RF signals revealed. Results show up to 5 %...