Basic knowledge on radiative and transport properties to begin in thermal plasmas modelling

Abstract

This paper has for objectives to present the radiative and the transport properties for people beginning in thermal plasmas. The first section will briefly recall the equations defined in numerical models applied to thermal plasmas; the second section will particularly deal with the estimation of radiative losses; the third part will quickly present the thermodynamics properties; and the last part will concern the transport coefficients (thermal conductivity, viscosity and electrical conductivity of the gas or mixtures of gases). We shall conclude the paper with a discussion about the validity of these results the lack of data for some specific applications, and some perspectives concerning these properties for non-equilibrium thermal plasmas. C 2015 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License. [http://dx

Nonequilibrium Phenomena in (Quasi-)thermal Plasma Flows

“…This challenge is evidenced by the determination of absorption coefficients. State-of-the art computations use millions of wavelength intervals [28], as exemplified by the work on microwave discharges of air, CO 2 , and CO 2 -H 2 mixtures by Kassir et al [42], and on plasmas containing metal vapors by Gleizes and Cressault [37]. Moreover, Planck's emission law is not valid for a system in NLTE, and radiative emission is function of the local thermodynamic state.…”

State of Art and Challenges for the Calculation of Radiative and Transport Properties of Thermal Plasmas in HVCB

“…Since, more studies on the radiative transfer equation have been done for pure gases (SF 6 , N 2 , Air, CO 2 ), binary mixtures (SF 6 -C 2 F 4 , C 4 F 8 -CO 2 , CO 2 -Cu [3,24]) and ternary mixtures (SF 6 -C 2 F 4 -Cu/W) in 1D-2D-3D geometry with imposed temperatures profiles [25][26][27][28]. An example is given in Figure 1 for the divergence of the flux for a SF 6 pure plasma at 1bar, obtained with different approached methods [1].…”

Radiative properties of ceramic metal-halide high intensity discharge lamps containing additives in argon plasma

“…The radiation coming from the continuum is due to freebound and free-free transitions. 1,9) The radiative recombination is calculated with the knowledge of the Biberman factors (for argon species only 10) ). As this factor is not available in the literature for other atomic species, we applied the hydrogen-like approach 11) with the knowledge of the energy levels, the statistical weights and the quantum numbers issued from NIST 12) and Kurucz et Peyterman databases.…”

“…1) In order to reduce the computing time, we did not use the line-by-line approach and preferred to use the approximation of the escape factor even if the corresponding emission can be overestimated depending on the pressure. 38) According to Drawin and Emard, 9) this factor was previously computed as a function of optical depths and broadening phenomena: the Doppler broadening, the pressure effects (resonance and Van der Waals broadenings) and the Stark broadening. 9) As conclusion, we elaborated a complete data bank including the properties of 25068 atomic lines: 11705 lines for argon species (Ar, Ar + , Ar 2+ , Ar 3+ ), 438 for mercury (Hg, Hg + ), 5159 for calcium (Ca, Ca + , Ca 2+ , Ca 3+ ), 1392 for sodium (Na, Na + , Na 2+ , Na 3+ ), 1459 for tungsten (W, W + , W 2+ ), 717 for Dysprosium (Dy, Dy + ), 181 for strontium (Sr, Sr + ), and 17 lines for Thallium (Tl, Tl + ), Iodine was neglected.…”