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“Similarities and differences between gliding glow and gliding arc discharges”. Kolev S, Bogaerts A, Plasma sources science and technology 24, 065023 (2015). http://doi.org/10.1088/0963-0252/24/6/065023
Abstract: In this work we have analyzed the properties of a gliding dc discharge in argon at atmospheric pressure. Despite the usual designation of these discharges as ‘gliding arc discharges’, it was found previously that they operate in two different regimes—glow and arc. Here we analyze the differences in both regimes by means of two dimensional fluid modeling. In order to address different aspects of the discharge operation, we use two models—Cartesian and axisymmetric in a cylindrical coordinate system. The obtained results show that the two types of discharges produce a similar plasma column for a similar discharge current. However, the different mechanisms of plasma channel attachment to the cathode could produce certain differences in the plasma parameters (i.e. arc elongation), and this can affect gas treatments applications.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.302
Times cited: 12
DOI: 10.1088/0963-0252/24/6/065023
Additional Links: UA library record; WoS full record; WoS citing articles
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“Three-dimensional modeling of energy transport in a gliding arc discharge in argon”. Kolev S, Bogaerts A, Plasma Sources Science &, Technology 27, 125011 (2018). http://doi.org/10.1088/1361-6595/aaf29c
Abstract: In this work we study energy transport in a gliding arc discharge with two diverging flat
electrodes in argon gas at atmospheric pressure. The discharge is ignited at the shortest electrode gap and it is pushed downstream by a forced gas flow. The current values considered are relatively low and therefore a non-equilibrium plasma is produced. We consider two cases, i.e. with high and low discharge current (28 mA and 2.8mA), and a constant gas flow of 10 lmin −1 , with a significant turbulent component to the velocity. The study presents an analysis of the various energy transport mechanisms responsible for the redistribution of Joule heating to the plasma species and the moving background gas. The objective of this work is to provide a general understanding of the role of the different energy transport mechanisms in arc formation and sustainment, which can be used to improve existing or new discharge designs. The work is based on a three-dimensional numerical model, combining a fluid plasma model, the shear stress transport Reynolds averaged Navier–Stokes turbulent gas flow model, and a model for gas thermal balance. The obtained results show that at higher current the discharge is constricted within a thin plasma column several hundred kelvin above room temperature, while in the low- current discharge the combination of intense convective cooling and low Joule heating prevents discharge contraction and the plasma column evolves to a static non-moving diffusive plasma, continuously cooled by the flowing gas. As a result, the energy transport in the two cases is determined by different mechanisms. At higher current and a constricted plasma column, the plasma column is cooled mainly by turbulent transport, while at low current and an unconstricted plasma, the major cooling mechanism is energy transport due to non-turbulent gas convection. In general, the study also demonstrates the importance of turbulent energy transport in redistributing the Joule heating in the arc and its significant role in arc cooling and the formation of the gas temperature profile. In general, the turbulent energy transport lowers the average gas temperature in the arc, thus allowing additional control of thermal non-equilibrium in the discharge. Keywords: A1 Journal Article; gliding arc discharge, sliding arc discharge, energy transport, fluid plasma model, atmospheric pressure plasmas; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ;
Impact Factor: 3.302
DOI: 10.1088/1361-6595/aaf29c
Additional Links: UA library record; WoS full record; WoS citing articles
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“A 2D model for a gliding arc discharge”. Kolev S, Bogaerts A, Plasma sources science and technology 24, 015025 (2015). http://doi.org/10.1088/0963-0252/24/1/015025
Abstract: In this study we report on a 2D fluid model of a gliding arc discharge in argon. Despite the 3D nature of the discharge, 2D models are found to be capable of providing very useful information about the operation of the discharge. We employ two modelsan axisymmetric and a Cartesian one. We show that for the considered experiment and the conditions of a low current arc (around 30 mA) in argon, there is no significant heating of the cathode surface and the discharge is sustained by field electron emission from the cathode accompanied by the formation of a cathode spot. The obtained discharge power and voltage are relatively sensitive to the surface properties and particularly to the surface roughness, causing effectively an amplification of the normal electric field. The arc body and anode region are not influenced by this and depend mainly on the current value. The gliding of the arc is modelled by means of a 2D Cartesian model. The arcelectrode contact points are analysed and the gliding mechanism along the electrode surface is discussed. Following experimental observations, the cathode spot is simulated as jumping from one point to another. A complete arc cycle is modelled from initial ignition to arc decay. The results show that there is no interaction between the successive gliding arcs.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.302
Times cited: 34
DOI: 10.1088/0963-0252/24/1/015025
Additional Links: UA library record; WoS full record; WoS citing articles
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