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Title: Nonuniqueness of two-temperature Guldberg-Waage and Saha equations: Influence on thermophysical properties of SF{sub 6} plasmas

This paper focuses to study how the choice of Guldberg-Waage and Saha equations affects the thermodynamic properties and transport coefficients of SF{sub 6} plasmas under both thermal equilibrium and non-equilibrium conditions. The species composition is numerically determined using two typical forms of two-temperature Saha equations and Guldberg-Waage equations that have appeared in the literature. The great influence of the choice of the excitation temperature on the plasma composition and hence the thermodynamic properties and transport coefficients is discussed as well. Transport coefficients are calculated with most recent collision interaction potentials by adopting Devoto's electron and heavy particle decoupling approach but expanded to the third-order approximation (second-order for viscosity) within the framework of Chapman-Enskog method. Furthermore, an analysis of the effect of different definitions of Debye length on the properties values was performed as well. The results are computed for various values of pressures from 0.10 atm to 10 atm and non-equilibrium parameter, i.e., ratio of the electron temperature to the heavy particle temperature from 1 to 5 with electron temperature range from 300 to 40 000 K. Both forms of Guldberg-Waage and Saha equations used here can give completely the same value when the two-temperature model reaches the special casemore » of local thermodynamic equilibrium. It has been observed that all above mentioned factors can significantly modify the plasma species composition and consequently affect the thermodynamic and transport properties.« less
Authors:
 [1] ;  [2] ;  [3] ;  [4]
  1. Qian Xuesen Laboratory of Space Technology, China Academy of Space Technology, Beijing 100094 (China)
  2. (China)
  3. State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an Jiaotong University, Xi'an, Shaanxi 710049 (China)
  4. Department of Electrical Engineering and Electronics, The University of Liverpool, Brownlow Hill, Liverpool L69 3GJ (United Kingdom)
Publication Date:
OSTI Identifier:
22218457
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 20; Journal Issue: 11; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; APPROXIMATIONS; CHARGED-PARTICLE TRANSPORT; DEBYE LENGTH; ELECTRON TEMPERATURE; ELECTRONS; EXCITATION; ION TEMPERATURE; LTE; NUMERICAL ANALYSIS; PLASMA; POTENTIALS; SAHA EQUATION; SULFUR FLUORIDES; THERMODYNAMIC PROPERTIES; VISCOSITY