International Journal of
Physical Sciences

  • Abbreviation: Int. J. Phys. Sci.
  • Language: English
  • ISSN: 1992-1950
  • DOI: 10.5897/IJPS
  • Start Year: 2006
  • Published Articles: 2572

Full Length Research Paper

Minimum time to use the fluid model in dc electrical discharges

B. Ardjani* and B. Liani
Laboratory of Theoretical Physics, Science Faculty, Tlemcen University, P. O. Box 119, 13000 Tlemcen, Algeria.  
Email: [email protected]

  •  Accepted: 13 August 2012
  •  Published: 30 May 2013


In the study of thermal equilibrium of the electrons, it is very necessary to use the fluid model method. In this work, effect of the gas density, the electrons initial energy and the electric field on the electron thermal equilibrium is studied. It is found that the steady state can be achieved by increasing the gas density or the inter-electrode distance. If the gas density or the inter-electrode distance are not sufficient, steady state can be achieved by increasing the electric field. The initial energy of the electrons has great effect on the steady state if the electric field is weak and the difference between the initial energy and the electrons mean energy is great, however this problem can be solved by extending the time. It is necessary to make a best combination between the gas density, inter-electrode distance and the electric field to make a modeling by the fluid model method in the best cases of the steady state. A simple formula is given here to find the minimum time required to use the fluid model for E/N ≥ 500 Td.


Key words: Electrons thermal equilibrium, transport properties, fluid model.