Modelling of the Plasma–Sheath Boundary Region in Wall-Stabilized Arc Plasmas: Unipolar Discharge Properties
A two-dimensional model of the non-equilibrium unipolar discharge occurring in the plasma–sheath boundary region of a transferred-arc was developed. This model was used to study the current transfer to the nozzle (1 mm diameter) of a 30 A arc cutting torch operated with oxygen. The energy balance an...
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2018
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| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_02724324_v38_n1_p147_Mancinelli http://hdl.handle.net/20.500.12110/paper_02724324_v38_n1_p147_Mancinelli |
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paper:paper_02724324_v38_n1_p147_Mancinelli |
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paper:paper_02724324_v38_n1_p147_Mancinelli2023-06-08T15:25:02Z Modelling of the Plasma–Sheath Boundary Region in Wall-Stabilized Arc Plasmas: Unipolar Discharge Properties Plasma–sheath Unipolar discharge Wall-stabilized arc Collisional plasmas Dissociation Electric fields Electron energy levels Electrons Energy dissipation Gas heating Hard facing Impact ionization Ionization of gases Ions Oxygen cutting Photodissociation Positive ions Discharge properties Dissociative ionization Electron attachment Electron energy loss Elementary reaction Inelastic collision Two dimensional model Wall-stabilized arc Electric discharges A two-dimensional model of the non-equilibrium unipolar discharge occurring in the plasma–sheath boundary region of a transferred-arc was developed. This model was used to study the current transfer to the nozzle (1 mm diameter) of a 30 A arc cutting torch operated with oxygen. The energy balance and chemistry processes in the discharge were described by using a kinetic block of 45 elementary reactions and processes with the participation of 13 species including electronically excited particles. The nonlocal transport of electrons was accounted for into the fluid model. The dependence of the ion mobility with the electric field was also considered. Basic discharge properties were described. It has been found that a large part (~ 80%) of the total electric power (1700 mW) delivered in the bulk of the sheath region is spent in heating the positive ions and further dissipated through collisions with the neutral particles. The results also showed that the electron energy loss in inelastic collisions represents only ~ 25% of the electron power and that about 63% of the power spent on gas heating is produced by the ion–molecule reaction, the electron–ion and ion–ion recombination reactions, and by the electron attachment. The rest of the power converted into heat is contributed by dissociation by electron-impact, dissociative ionization and quenching of O(1D). Some fast gas heating channels which are expected to play a key role in the double-arcing phenomena in oxygen gas were also identified. © 2017, Springer Science+Business Media, LLC. 2018 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_02724324_v38_n1_p147_Mancinelli http://hdl.handle.net/20.500.12110/paper_02724324_v38_n1_p147_Mancinelli |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Plasma–sheath Unipolar discharge Wall-stabilized arc Collisional plasmas Dissociation Electric fields Electron energy levels Electrons Energy dissipation Gas heating Hard facing Impact ionization Ionization of gases Ions Oxygen cutting Photodissociation Positive ions Discharge properties Dissociative ionization Electron attachment Electron energy loss Elementary reaction Inelastic collision Two dimensional model Wall-stabilized arc Electric discharges |
| spellingShingle |
Plasma–sheath Unipolar discharge Wall-stabilized arc Collisional plasmas Dissociation Electric fields Electron energy levels Electrons Energy dissipation Gas heating Hard facing Impact ionization Ionization of gases Ions Oxygen cutting Photodissociation Positive ions Discharge properties Dissociative ionization Electron attachment Electron energy loss Elementary reaction Inelastic collision Two dimensional model Wall-stabilized arc Electric discharges Modelling of the Plasma–Sheath Boundary Region in Wall-Stabilized Arc Plasmas: Unipolar Discharge Properties |
| topic_facet |
Plasma–sheath Unipolar discharge Wall-stabilized arc Collisional plasmas Dissociation Electric fields Electron energy levels Electrons Energy dissipation Gas heating Hard facing Impact ionization Ionization of gases Ions Oxygen cutting Photodissociation Positive ions Discharge properties Dissociative ionization Electron attachment Electron energy loss Elementary reaction Inelastic collision Two dimensional model Wall-stabilized arc Electric discharges |
| description |
A two-dimensional model of the non-equilibrium unipolar discharge occurring in the plasma–sheath boundary region of a transferred-arc was developed. This model was used to study the current transfer to the nozzle (1 mm diameter) of a 30 A arc cutting torch operated with oxygen. The energy balance and chemistry processes in the discharge were described by using a kinetic block of 45 elementary reactions and processes with the participation of 13 species including electronically excited particles. The nonlocal transport of electrons was accounted for into the fluid model. The dependence of the ion mobility with the electric field was also considered. Basic discharge properties were described. It has been found that a large part (~ 80%) of the total electric power (1700 mW) delivered in the bulk of the sheath region is spent in heating the positive ions and further dissipated through collisions with the neutral particles. The results also showed that the electron energy loss in inelastic collisions represents only ~ 25% of the electron power and that about 63% of the power spent on gas heating is produced by the ion–molecule reaction, the electron–ion and ion–ion recombination reactions, and by the electron attachment. The rest of the power converted into heat is contributed by dissociation by electron-impact, dissociative ionization and quenching of O(1D). Some fast gas heating channels which are expected to play a key role in the double-arcing phenomena in oxygen gas were also identified. © 2017, Springer Science+Business Media, LLC. |
| title |
Modelling of the Plasma–Sheath Boundary Region in Wall-Stabilized Arc Plasmas: Unipolar Discharge Properties |
| title_short |
Modelling of the Plasma–Sheath Boundary Region in Wall-Stabilized Arc Plasmas: Unipolar Discharge Properties |
| title_full |
Modelling of the Plasma–Sheath Boundary Region in Wall-Stabilized Arc Plasmas: Unipolar Discharge Properties |
| title_fullStr |
Modelling of the Plasma–Sheath Boundary Region in Wall-Stabilized Arc Plasmas: Unipolar Discharge Properties |
| title_full_unstemmed |
Modelling of the Plasma–Sheath Boundary Region in Wall-Stabilized Arc Plasmas: Unipolar Discharge Properties |
| title_sort |
modelling of the plasma–sheath boundary region in wall-stabilized arc plasmas: unipolar discharge properties |
| publishDate |
2018 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_02724324_v38_n1_p147_Mancinelli http://hdl.handle.net/20.500.12110/paper_02724324_v38_n1_p147_Mancinelli |
| _version_ |
1768544863759892480 |