Дисертації з теми "Electric Arc Plasma"
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Javidi, Shirvan Alireza. "Modelling of Electric Arc Welding : arc-electrode coupling." Licentiate thesis, Högskolan Väst, Avd för maskinteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-5826.
Повний текст джерелаAula, M. (Matti). "Optical emission from electric arc furnaces." Doctoral thesis, Oulun yliopisto, 2016. http://urn.fi/urn:isbn:9789526210926.
Повний текст джерелаTiivistelmä Valokaariuunien ohjaus on perinteisesti ollut uunioperaattorin käsissä. Valokaaariuuniprosessin on-line mittaukseen on olevassa vähän menetelmiä johtuen uunin hyvin haastavaista olosuhteista. Tässä työssä on tutkittu optiseen emissiospektroskopiaan perustuvaa menetelmää uuden jatkuva-aikaisen tiedon tuottamisessa valokaariuuniprosessista. Mittausjärjestelmä perustuu valon keräämiseen mitattavasta uunista valokuidun avulla, joka johtaa valon analysoitavaksi etäälle prosessista sijoitettuun spektrometriin. Mittauksia suoritettiin laboratorio-, pilot- ja tehdas-mittakaavassa. Valokaariuunin kuonan koostumuksen analysointia testattiin laboratorio- ja pilot-mittakaavan uuneilla. Laboratoriomittaukset osoittivat että kuonan komponenteista CrOx ja MnO ja vaikuttavat eniten mitattuun emissiospektriin. Pilot-mittakaavan kokeissa havaittiin, että kuonan Cr2O3-pitoisuutta voidaan mitata valokaaren emissiospektristä 0,62 %-yksikön keskimääräisellä absoluuttisella virheellä ja 0,49 %-yksikkön hajonnalla. Teollisella valokaariuunilla suoritetuista mittauksista havaittiin että optisen emissiospektrin mittaus voidaan suorittaa ilman ylitsepääsemättömiä teknisiä esteitä. Mittauksen tuloksia voidaan puolestaan käyttää kaasufaasin reaktioiden, romun sulamisen ja kuonapinnan ominaisuuksien arvioinnissa. Valokaaren emissiospektrin analyysi osoitti, että valokaaren plasman komponentit ovat pääosin peräisin kuonasta, joka mahdollistaa kuonan koostumuksen arvioinnin valokaaren emissiospektrin perusteella. Romun sulamisen mittausta voidaan prosessinohjauksessa käyttää jänniteportaiden ja toisen korin panostuksen optimointiin. Kuonan kromipitoisuuden mittaamista voidaan puolestaan käyttää pelkistinaineiden lisäyksen optimointiin ja kuonan jatkokäsittelyn valintaan
Lisnyak, Marina. "Theoretical, numerical and experimental study of DC and AC electric arcs." Thesis, Orléans, 2018. http://www.theses.fr/2018ORLE2013/document.
Повний текст джерелаThe ignition of an electric arc in the electric distribution system of an aircraft can be a serious problem for flight safety. The amount of information on this topic is limited, however. Therefore,the aim of this work is to investigate the electric arc behavior by means of experiment and numerical simulations.The MHD model of the LTE arc column was used and resolved numerically using the commercial software comsol Multiphysics. In order to describe plasma-electride interaction, the model had to be extended to include non-equilibrium effects near the electrodes. These zones were taken into account by means of current and energy conservation in the non-equilibrium layer. The correct matching conditions were developed and are described in the work. Validation of the model in the case of a free burning arc showed excellent agreement between comprehensive models and the experiment.This model was then extended to the case of the electric arc between rail electrodes in a 3D geometry. Due to electromagnetic forces the electric arc displaces along the electrodes. A self-consistent description of this phenomenon was established. The calculation was performed for DC, pulsed and AC current conditions at atmospheric and lower pressures. The main characteristics of the arc were analyzed and discussed. The results obtained were compared with the experimental measurements and showed good agreement.The model of electric arcs between busbar electrodes is able to predict the behavior of a fault arc in aeronautical conditions. Further improvements of the model are discussed as an outlook of the research
Coulombe, S. (Sylvain). "A model of the electric arc attachment on non-refractory (cold) cathodes /." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=34710.
Повний текст джерелаKrolak, Matthew Joseph. "Optimization of a magnetoplasmadynamic arc thruster." Link to electronic thesis, 2007. http://www.wpi.edu/Pubs/ETD/Available/etd-042607-155701/.
Повний текст джерелаSousa, martins Rafael Alexandre. "Etude expérimentale et théorique d'un arc de foudre et son interaction avec un matériau aéronautique." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLC080/document.
Повний текст джерелаNowadays, the study of the direct effects of lightning on aeronautical structures could be based, at least in part, on simulation tools. Nevertheless, the lack of experimental data on the transient phase of the lightning arc does not allow us to justify the predictive nature of the simulation tools. The objective of this thesis is to produce an experimental database based on the characterization of lightning arcs in standardized situations. These data can be used both for the understanding of the phenomena observed during the tests, but especially as a reference comparable to the simulation tools.First, we are interested in the free arc column in air, without interaction with the electrodes. Furthermore, time- and space-resolved profilesof temperature and pressure are evaluated by emission spectroscopy. For a 100 kA arc, it is shown that the temperature reaches 37400 K in the arc axis at 2 μs after arc ignition, with a corresponding pressure of 45 bar.Second, we are interested in the interaction of the lightning arc with aeronautical materials. The dynamics of the arc roots and the characteristics of the shock wave are analyzed for different aeronautical materials such as aluminum or carbon fiber composites. The thermo-mechanical constraints applied on the material are studied by infrared thermography and by rapid deflection measurements at the center of panel, leading to an evaluation of the pressure exercised by the arc at the attachment point
Hameurlaine, Kheira. "Contribution à l'étude d'un arc électrique de faible puissance." Phd thesis, Université d'Orléans, 2012. http://tel.archives-ouvertes.fr/tel-00821030.
Повний текст джерелаTrenty, Laurent. "Modélisation du chauffage de bains métalliques par un plasma d'arc transféré." Châtenay-Malabry, Ecole centrale de Paris, 1997. http://www.theses.fr/1997ECAP0510.
Повний текст джерелаFleury, Emmanuel. "Etude d'un plasma de méthane en atmosphère non oxydante." Rouen, 1988. http://www.theses.fr/1988ROUES004.
Повний текст джерелаLu, Jingjing. "Caractérisation du comportement du plasma dans un disjoncteur basse tension par le développement d'un outil numérique et d'expériences associées." Thesis, Toulouse 3, 2020. http://www.theses.fr/2020TOU30154.
Повний текст джерелаThe arc splitting process and the quantification of additional voltage drops are the major phenomena to understand and to optimize the Low Voltage Circuit Breaker (LVCB). The aim of our work is to understand their behavior through experiments and then their representation by our model. Therefore, a three-dimensional (3D) magnetohydrodynamic modeling is carried out on a simplified LVCB geometry. The developments are based on the commercial code Ansys @Fluent with UDF (User Define Functions). The plasma is described by fluid equations and a finite volume method. To study and isolate the mechanisms, the experimental and numerical work were realized on a simplified geometry, composed by two parallel electrodes with or without splitter plates. Numerically, the additional voltage resulting from the sheaths at the plasma/material interfaces, is considered by an approximate method based on the theoretical characteristic of voltage variation, as the function of current density. This additional resistivity allows to present the current flow in the materials and create some delay at the switching during the splitting process. Further to the experiments, the arc behavior is characterized by electrical measurements (Voltage, current) and by high-speed camera. The arc ignition is realized by a copper fuse of 0.1 mm. The geometry can be more or less closed at its both extremities in order to highlight the effects of pressure force and/or Lorentz force. The description of arc behavior was found similar between the simulation and experiments results. However, the initial conditions of our model proved to be preponderate while at the same time, the conditions remained delicate to determine
Samohejl, Matěj. "Rozšíření možností optické diagnostiky spínacího oblouku." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-242055.
Повний текст джерелаElayoubi, Mustapha. "Transfert d'atomes d'hydrogène vers la cathode d'un arc réducteur de composition argon-hydrogène /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1989. http://theses.uqac.ca.
Повний текст джерелаRazafinimanana, Manitra. "Etude des proprietes d'un plasma d'arc dans les melanges hexafluorure de soufre-azote (sf : :(6)-n::(2))." Toulouse 3, 1986. http://www.theses.fr/1986TOU30240.
Повний текст джерелаKasal, Ondřej. "Zjednodušený model axiálně chlazeného oblouku." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-218009.
Повний текст джерелаRichard, Frédéric. "Etude et caracterisation d'une decharge electrique glissante dans l'air a pression atmospherique." Orléans, 1995. http://www.theses.fr/1995ORLE2061.
Повний текст джерелаGongassian, Michel. "Etude theorique du rayonnement emis par un plasma d'hexafluorure de soufre." Toulouse 3, 1986. http://www.theses.fr/1986TOU30066.
Повний текст джерелаSAKALIS, IOANNIS V. "Contribution a l'etude du pouvoir de coupure de l'hexafluorure de soufre et des melanges hexafluorure de soufre-azote." Toulouse 3, 1986. http://www.theses.fr/1986TOU30068.
Повний текст джерелаOUAJJI, HASSAN. "Etude de proprietes de transport d'un plasma de melange air-cuivre : modelisation de la colonne d'arc." Clermont-Ferrand 2, 1986. http://www.theses.fr/1986CLF21034.
Повний текст джерелаSAUVAGE, BRUNO. "Etude des plasmas d'arc d'hydrogene/methane : application a l'hydropyrolyse d'hydrocarbures lourds." Toulouse 3, 1989. http://www.theses.fr/1989TOU30012.
Повний текст джерелаMaouhoub, Essaadia. "CONTRIBUTION A L'ETUDE DE L'INFLUENCE DE LA MOLECULE DE CO2 SUR UN PLASMA DE MELANGE Ar-CO2,ETUDE EXPERIMENTALE DE LA REPARTITION RADIALE DESTEMPERATURES DANS UN PLASMA Ar-CO2." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 1997. http://tel.archives-ouvertes.fr/tel-00174390.
Повний текст джерелаLa partie expérimentale constitue la partie principale et essentielle de ce travail. Nous avons mis au point la chambre à arc stabilisé par parois (type Maecker modifié) afin de disposer d'un arc stable dans le temps. Les méthodes de diagnostic du plasma sont basées sur la spectroscopie d'émission. Deux méthodes d'interpolation (polynôme, spline) pour le lissage des points expérimentaux sont comparées. Les profils de températures d'excitation sont détermines à partir des raies atomiques (argon, carbone, oxygène) et les profils de température de rotation à partir des spectres moléculaires observés, système de Swan C2(0,0) et système violet de CN(0,0).
Les principaux résultats expérimentaux obtenus montrent que :
-la composition locale du plasma n'est pas celte injectée,
- la température augmente en fonction du courant,
-le gradient de température diminue quand le courant augmente,
-les formes des profils des températures d'excitation sont modifiées pour le plasma du mélange Ar-CO2
-le gradient de température diminue quand on augmente te pourcentage de CO2,
- la formation d'un noyau à température élevée sur l'axe de la décharge et d'un début de palier entre 7 000k et 8 500 K,
- les températures de rotations sont vraisemblablement celtes de la périphérie.
Bultel, Arnaud. "Analyse d'un plasma d'azote basse pression en situations de jet libre et de couche limite." Rouen, 1994. http://www.theses.fr/1994ROUE5007.
Повний текст джерелаZhan, Yiyi. "PC-based visual simulation of high pressure arc plasma." Thesis, University of Liverpool, 2011. http://livrepository.liverpool.ac.uk/3433/.
Повний текст джерелаKahhali, Nicolas. "Modélisation et simulations numériques du transfert radiatif dans les plasmas d'arc électrique." Thesis, Châtenay-Malabry, Ecole centrale de Paris, 2009. http://www.theses.fr/2009ECAP0023/document.
Повний текст джерелаNon fourni
Marboutin, Yves. "Contribution à l'étude et à l'optimisation d'une torche à plasma à arc non transféré." Thesis, Clermont-Ferrand 2, 2012. http://www.theses.fr/2012CLF22256/document.
Повний текст джерелаThe context of this thesis is the production of hydrogen as an energy vector by steam thermolysis consisting in the dissociation of H2O molecule into oxygen (O) and hydrogen (H). The process used is a plasma torch device developed by the LAEPT. After presenting the theory of plasma physics and atomic emission spectroscopy which will help to make the most of the measured realized, this thesis will show the evolution of the plasma torch device and the experimental environment required to work with explosive and unstable gases. Some measurements like electrical, hydraulic and spectroscopy magnitudes made it possible to determine the chemical and physical characteristics of a water vapor – argon plasma. A comparison between experiments and theoretical knowledge will enable to determine the temperature of a flow of plasma, electrical conductivity, enthalpy and the electronic density
Rehmet, Christophe. "Étude théorique et expérimentale d’une torche plasma triphasée à arcs libres associée à un procédé de gazéification de matière organique." Thesis, Paris, ENMP, 2013. http://www.theses.fr/2013ENMP0041/document.
Повний текст джерелаArc plasma torches are widely used in industrial applications. A 3-phase AC plasma technology with consumable graphite electrodes is under development at PERSEE MINES - ParisTech. This technology noticeably differs from the classical DC plasma torches and aims at overcoming a number of limits of plasma systems in terms of reliability, equipment and operating costs. In order to improve the understanding of the unsteady physical phenomena in such plasma systems, a theoretical and experimental study is conducted under non reactive condition (nitrogen, syngas). Experimental study is based on high speed video camera (100 000 frames per second) and electrical signal analyses. Theoretical analysis is based on 3D unsteady Magneto-Hydro-Dynamic (MHD) model of the arc zone using CFD software Code_Saturne®, by a parametric study based on current, frequency and plasma gas flow rate influence. Two configurations: coplanar and parallel electrodes are studied. These studies highlight the influence of electromagnetic and hydrodynamic phenomena on the arc motion. In coplanar electrode configuration, electrode jets appear to be the dominant parameter on the arc motion, heat transfer and arc ignition. In the parallel electrodes configuration, the motion of the hot channel seems to be the key parameter. Comparison between MHD modeling and experimental results shows a fair correlation, both in accordance with the arc behavior and the electrical waveform
Schonjahn, Cornelia. "Surface treatment in a cathodic arc plasma : key step for interface engineering." Thesis, Sheffield Hallam University, 2001. http://shura.shu.ac.uk/20336/.
Повний текст джерелаTroughton, Samuel Christopher. "Phenomena associated with individual discharges during plasma electrolytic oxidation." Thesis, University of Cambridge, 2019. https://www.repository.cam.ac.uk/handle/1810/288879.
Повний текст джерелаGeorge, Jonathan Alan. "Development of a Plasma Arc Manufacturing Process and Machine to Create Metal Oxide Particles in Water From Wire Feedstock." Diss., CLICK HERE for online access, 2010. http://contentdm.lib.byu.edu/ETD/image/etd3494.pdf.
Повний текст джерелаMitiche, Moh Djerdjer. "Modelisation d'un arc de disjoncteur a sf : :(6) au passage a zero du courant." Toulouse 3, 1988. http://www.theses.fr/1988TOU30152.
Повний текст джерелаHermette, Loïc Deva. "Etude de l'impact des vapeurs métalliques et organiques sur les propriétés d'un arc de disjoncteur haute-tension." Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30377/document.
Повний текст джерелаThe High Voltage Circuit Breaker (HVCB) represents one of the most important and complex components in the energy transmission, it must be there to isolate faulted section of a network, interrupt fault and abnormal currents: due to non-linear loads (for example arc furnace) or other load variation. Nowadays, to reduce the cost of HVCB development, the numerical model based on physical considerations is used for designing circuit-breakers. However, whatever the operating conditions, the arc does not establish in pure SF6, which is currently the dielectric gas used in the HVCB. In fact, during the interrupting phase the electrical arc is established between metallic electrodes (Cu) and quenched inside a nozzle composed by PTFE (C2F4), this electrical arc is an energetic environment which ablates the PTFE issue from wall and erodes copper issue from electrode. How it has been reported by several authors, the presence of organic and/or metallic vapours in the plasma modifies the properties of this one. Recent works have proved the impact of the PTFE vapour on the rise of pressure and the arc blown. Furthermore, the presence of metallic vapours has an important impact on the electrical conductivity and radiation emission. The calculation of the electrical arc properties composed by SF6-C2F4-Cu and SF6-C2F4-W has been performed for pressures up to 250 bars, temperatures between 300K and 30 000K and various mass concentrations with the assumption of Local Thermodynamic Equilibrium (LTE). The first part of this thesis give a presentation of the High-Voltage Circuit Breaker. The second part of this thesis is devoted to the calculation of the total atomic and molecular radiation. The third part is dedicated to the calculations of the transport, which have been calculated according to the Chapman-Enskog theory with the following approximations: third for electrical conductivity and for electron translational thermal conductivity, second for heavy species translational thermal conductivity, and first for reactional thermal and viscosity. Finally, we focus on the elaboration of mixing for our ternary mixture. Currently, calculating the plasma properties at each time and for all composition, pressure and temperature in a numerical model necessitate consequential calculation time. For these reasons, we have studied different mixing rules for the mixture SF6-C2F4-Cu and SF6-C2F4-W
Maulat, Catherine. "Etude par spectroscopie d'emission et spectroscopie laser du fonctionnement et des echecs de coupure d'un arc tournant de disjoncteur moyenne tension." Orléans, 1987. http://www.theses.fr/1987ORLE2041.
Повний текст джерелаLEVESQUE, PATRICK. "Etude des mecanismes physiques et des perturbations liees a l'attachement d'un arc electrique sur un cylindre conducteur." Paris 6, 1986. http://www.theses.fr/1986PA066318.
Повний текст джерелаKabbaj, Narjisse. "Etude du transfert radiatif d'un plasma thermique d'air : influence des propriétés radiatives dans la modélisation d'un arc libre." Thesis, Toulouse 3, 2019. http://www.theses.fr/2019TOU30024.
Повний текст джерелаIn the simulation of electrical arc, the representation of radiative contribution is essential to provide a satisfactory description of the thermal behavior of the plasma. The accurate prediction of the radiative emission is essential to determine the evolution of the arc temperature. For a precise description of radiative effect, a resolution of the Radiative Transfer Equation (RTE) , is necessary necessary with knowledge of the absorption coefficient. Unfortunatly, the complexity of this coefficient - dependent on temperature and wavelenghth- makes this equation impossible to solve in term of computational cost. This is why many approximative methods are developed to simplify the calculation of the radiative properties. In this work, we have carried out a detailed description of the spectrum of an air plasma with about 7.106 points on frequency. From this description, we have calculated the divergence of the radiative flux either from the net emission coefficient (NEC) based on a geometric simplification of the plasma, or from the mean absorption coefficients (MAC) calculated after a division of the spectrum into 6 intervals in which we have used different mean functions (Classic, Planck, Planck Modified and Rosseland), or from an exact calculation corresponding to a direct solution of the RTE. This is why many approximative methods were developed to reduce numerical demands . The calculations have been done for 9 simplified configurations in 1D assuming a cylindrical plasma for which the temperature profile varies only with the radius. The different steps of the work are presented and highlight the influence of several parameters such as the temperature profile, the pressure, the copper vapors.... A great part of this work deals with the comparison between the results obtained from the exact resolution with the results deduced from the other approaches in order to validate the use and the accuracy of the different methods. This comparison allowed us to develop an optimization methodology providing improvements to the calculation of the approximate methods (NEC and MAC) allowing a better description of the radiative properties. Finally, this work presents the development of an axisymmetric 2D free-burning arc model solving the Navier-Stockes and Maxwell equations by the finite volume method. This model allows a comparison between the NEC method and the P1 method which takes into account the absorption of radiation in the cold areas
El, Hamoui Mohamad A. "A Pipeline Analog-To-Digital Converter for a Plasma Impedance Probe." DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/287.
Повний текст джерелаHleli, Ali. "Étude de la cinétique chimique et des propriétés radiatives d'un plasma d'arc dédié à la synthèse de nanoparticules de carbone." Thesis, Toulouse 3, 2020. http://www.theses.fr/2020TOU30075.
Повний текст джерелаThe electric arc process or the quasi-thermal plasma is one of the most used to produce nanomaterials. The study of the physicochemical phenomena underlaying arcs can be achieved by means of collisional-radiative models to thoroughly describe the chemical composition with the use of the particles number conservation law in the plasma. This method allows a straightforward calculation of thermal properties. These models provide a realistic description of the arc-induced chemistry and allow better understanding of the deviations from local thermodynamic equilibrium. It is in this context that the present work is clearly situated, relating to develop multi-temperature numerical tools able to predict, the chemical composition of Ar-He-N2 mixtures in the presence of carbon, nickel and yttrium removal from electrodes, experimentally used for carbon nanotubes synthesis, and determine the radiative proprieties such as the emission spectra of the C2 Swan and the CN Violet systems frequently observed in nitrogen and carbon containing mixtures and useful for arc characterization and diagnostics : the determination of the rotational and the vibrational temperatures
Júnior, Adonias Ribeiro Franco. "Obtenção de revestimentos dúplex por nitretação a plasma e PVD-TiN em aços ferramenta AISI D2 e AISI H13." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/3/3133/tde-02102003-114623/.
Повний текст джерелаIn this work, the influence of both the microstructure and the load-bearing capacity of nitrided layers, formed on top of AISI D2 and AISI H13 tool steels, on adhesion and wear resistance of PVD-TiN coatings was studied. The threshold nitriding potential curves for the above mentioned steels and the optimum conditions of the pre-treatments which increased the adhesion as well as the wear resistance of the PVD-TiN were determined experimentally. By using longer nitriding times (about 11 h) and lower nitrogen contents in the gas mixture (about N2-5%vol.), it was possible to minimize the pile-up degree of the TiN/H13 nitrided substrates and, consequently, the occurrence of coatings chipping. This flaw persists when the nitrided layer is thin, due to an abrupt transition of mechanical properties at the TiN coating / steel core interface. Shorter nitriding times (about 42 min.) and lower nitrogen contents (about N2-5%vol.), on the other hand, are sufficient to guarantee a better adhesion of TiN coatings on AISI D2 tool steel, as the core of such steel possesses relatively better load-bearing capacity than the AISI H13 tool steel. The presence of a black layer at the TiN/nitrided layer interface was observed in all coatings deposited over nitrided layers produced above the threshold nitriding potential curves. This layer affects adversely the wear resistance and the adhesion of the TiN coatings. When higher loads are applied on the coated surface, egg shell type flaws easily occur.
Roccapriore, Kevin M. "Nanophotonics of Plasmonic and Two-Dimensional Metamaterials." Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1248498/.
Повний текст джерела(8114765), Yu Wang. "NUMERICAL MODELING OF THE METAL MELTING UTILIZING A DC ELECTRIC ARC PLASMA FOR ELECTRIC ARC FURNACE." Thesis, 2019.
Знайти повний текст джерелаThe electric arc furnace (EAF) is one of the most widely-used steelmaking process recycling the scrap as the raw material. Electric arc furnace steelmaking is a material-dependent and energy-consuming process. The electricity is utilized as the main heat source to melt the scrap by the electric arc discharging from the graphite electrodes. Since the plasma arc weld has the very similar heat transfer mechanism and melting phenomenon comparing with the scrap melting in EAF process, the model development for the free-burning arc, the arc-metal heat transfer, and the metal melting will refer to the research of plasma arc weld field and start with a relatively small scale. In this study, a comprehensive computational dynamics (CFD) model was developed to predict the heat transfer from the electric arc to the metal anode, which is composed of the DC electric arc model, solidification and melting model, and the arc-metal heat transfer model. The validation of the CFD models has been conducted utilizing the experimental data and simulation results in other literature. The commercial software, ANSYS FLUENT®, was employed with the User-Defined Function scripts and the User-Defined Scalar to model the magnetic field, comprehensive flow field, and high temperature field. Furthermore, the parametric studies for the process of the anode melted by the plasma arc were performed to investigate the effects of the arc current and the initial anode temperature on the anode melting. The results reveal that the value of the arc current has a positive correlation with the arc temperature and velocity but has negative correlation with the penetration time of the anode. Meanwhile, with the increase of anode initial temperature, the metal penetrate time will decrease.
"ARC FLASH DETECTION THROUGH VOLTAGE/CURRENT SIGNATURES." Thesis, 2012. http://hdl.handle.net/10388/ETD-2012-08-643.
Повний текст джерелаEkici, Özgür 1973. "Computational study of arc discharges : spark plug and railplug ignitors [sic]." 2007. http://hdl.handle.net/2152/11950.
Повний текст джерелаLi, Chen-Yang, and 李振陽. "Electrical and Optical Properties of ZnO:Ti Thin Films Prepared by Cathodic Arc Plasma Deposition System." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/01414514063170480957.
Повний текст джерела國立屏東科技大學
機械工程系所
98
In the transparent conductive film, ZnO film has a significant priority to grow c-axis orientation and transparency, and a low resistivity and good light penetration, which is widely used in electric and acoustic sound and light components. In addition, zinc oxide thin films with surface texture or the surface defects for application the optical device (such as: solar cells) due to enhanced light trapping (enhanced light trapping). The resistivity ZnO thin film is generally high (about 1-100 Ω-cm), and the main origin of its conductive properties are contributed by oxygen vacancies, interstitial zinc atom and the doped ions. The nature of ZnO thin films are deeply affected by their preparation. In this thesis study, titanium doped zinc oxide (Ti-doped ZnO) film is deposited a lower pressure in the vacuum system by cathodic arc plasma. This study mainly explores the effect of doping ZnO thin films and optical properties into the target power, the working atmosphere and the film thickness for the titanium. In this experiment, titanium doped zinc oxide(Ti -doped ZnO) films to inspect its microstructure, electricity and optical properties. First, ZnO thin films deposited under different target power, the deposition pressure 2 × 10-3, the crystalline permutation more compact, and have lower resistivity value of 9.8 × 10-2Ω-cm. ZnO thin films in visible light area can get the penetration rate over 80%, while the energy gap and carrier concentration are related to initial absorption by absorption spectrum peak at about (380 nm) , and the energy gap range is about 3.10 eV. In order to improve the device efficiency, the more resistance to further reduce the Bank rate is a necessary road. Due to the small amount of doping other metal ions can effectively improve the electrical properties of zinc oxide, so the future by doping a small amount of titanium deposited Ti-doped ZnO thin film , when under the target power of 700 watts on the zinc (W) and titanium target power of 700 watts (W), the small amount of doping other metal ions had the lowest resitivity at 4.8 × 10-3 Ω-cm, and Ti -doped ZnO thin films can get the penetration rate of 80 % or more. At the same time, the energy gap width of the 3.10 eV was increased to 3.27 eV and followed with the carrier concentration increases, a small amount of titanium doped ZnO thin films did improve the conductivity properties. Therefore, this study will also explore target power, the working atmosphere and the film thickness of the Ti-doped ZnO thin film properties, in order to achieve better coating conductivity and optical properties.
Huang, hun-Chih, and 黃俊智. "Electrical and Optical Properties of ZnO Thin Films Prepared by Cathodic Arc Plasma Deposition System." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/53701837391666230427.
Повний текст джерела國立屏東科技大學
機械工程系所
98
Zinc oxide (ZnO) thin film is a new generation of transparent conducting oxide thin film, the materials of zinc are not virulence and it is abundant in the nature, and the materials of zinc will be to replace the indium tin oxide (ITO) thin film, many methods for preparation of the TCO thin film, among these methods, the cathodic arc technique is rare, which can create ions and it has the highly energy, and the cathodic arc technique has highly deposition rate, therefore, the cahtodic arc technique is a choice for process of low-temperature or cost-down, that is why, our study used cathodic arc technique prepared ZnO thin films on glass and PET substrates, respective, and investigate the optical and electrical properties of ZnO thin films with the function of the target power、oxygen and film thicknesses. In our study prepared ZnO thin films on glass and PET substrates, respective, and the all samples of ZnO thin films with marked (002) peak, and highly transmittance over 80 % in the visible wavelength, preparation of ZnO thin films on glas substrates with various target power, and the resistivity of ZnO thin films is 6~8×10-3 Ω-cm ,the improved of the crystal size with various target power is not obvious, the optical energy gap shift to direction of the long-wavelength. Preparation of ZnO thin films on glas substrates with various oxygen gas flow rate, and the carrier mobility is decreasing in the parameter, the resistivity is 4~7 ×10-3 Ω-cm ,and the all samples of ZnO thin films with marked (002) peak, the optical properties of ZnO thin films is not obvious change, and the optical energy gap is 3.3 eV. Preparation of ZnO thin films on glas substrates with various thin films thicknesses, the carrier concentration and the carrier mobility improved with increasing thicknesses, and the carrier concentration is 6.25×1019~2.4×1020 cm-3 and the carrier mobility is 12.5~15.5 cm2 /V-S, the resistivity is 6~8×10-3 Ω-cm , preparation of ZnO thin films on PET substrates with various thin films thicknesses, the resistivity decreased with increasing thickness, the resistivity is 1.97×10-2~5.27×10-3 Ω-cm and the optical energy gap is 3.29~3.24 eV.