Continuous phase transition in the region of the vacuum arc cathode spot

Journal Article · Mon Sep 15 00:00:00 EDT 2008 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.2981318· OSTI ID:21269076

Askari, S; Minoo, H ^[1]; Moussakhani, K ^[2]

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1. Department of Physics, KNT University, Tehran 19697 (Iran, Islamic Republic of)
2. Department of Electrical Engineering, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of)

A model for the near-cathode region of electric arcs is presented to investigate the liquid-plasma phase transition in the cathode spot region. Due to the high values of pressure and temperature after spot ignition, a 'continuous phase transition' occurs in the liquid-vapor interface. A set of fluid equations with suitable boundary conditions have been solved to obtain diagrams of the spot plasma in the temperature-density plane during the spot evolution for a typical spot. To evaluate the model, the magnitude of some essential quantities such as the mean ion charge state of plasma and current density have been calculated, which are in accordance with experimental results.

• OSTI ID: 21269076
• Journal Information: Physics of Plasmas, Vol. 15, Issue 9; Other Information: DOI: 10.1063/1.2981318; (c) 2008 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
BOUNDARY CONDITIONS
CATHODES
CHARGE STATES
CURRENT DENSITY
ELECTRIC ARCS
IONS
LIQUIDS
PHASE TRANSFORMATIONS
PLASMA
PLASMA PRESSURE
PLASMA SIMULATION
VAPORS