Modelling interaction of multispecies plasmas with thermionic cathodes

Abstract

The model of the near-cathode plasma, developed previously for the case of a single-species plasma-producing gas, is generalized for the case of multiple plasma-producing species. Results are presented of calculation of a diffuse mode of current transfer to tungsten cathodes in a mercury plasma with an addition of sodium. It is found that the presence of 1% of sodium results in a considerable expansion of the range of stability of the diffuse mode.

Understanding and modelling plasma–electrode interaction in high-pressure arc discharges: a review

“…Let us now consider recent models of the near-cathode layer on the whole. There are three models with a collisionless space-charge sheath: the model formulated in [37] and modified in [23,50] (a summary of equations of this model can be found in [51]), the model [52] and the model [53]. There is also a model [16], which is similar to [37] except that the ion motion across the space-charge sheath is treated as collision-dominated and the sheath is described by means of the solution [38].…”

Computing Different Modes on Cathodes of DC Glow and High‐Pressure Arc Discharges: Time‐Dependent Versus Stationary Solvers

“…Numerical results reported in this work refer to arcs burning in argon and cathodes made of tungsten. The near‐cathode plasma layer was calculated by means of the formulas summarized in ref . Data on thermal conductivity and emissivity of tungsten have been taken from refs., respectively.…”

“…The nearcathode plasma layer was calculated by means of the formulas summarized in ref. [19] Data on thermal conductivity and emissivity of tungsten have been taken from refs., [20,21] respectively.…”

Joule heat generation in thermionic cathodes of high-pressure arc discharges

“…Functions q p ðT w ; UÞ and jðT w ; UÞ are evaluated by means of a model of the near-cathode plasma layer described in Ref. 17. Data on thermal conductivity and emissivity of tungsten have been taken from Refs.…”