Propriétés thermodynamiques et de transport des plasmas issus de la vaporisation des isolants PTFE et PE

Abstract

At atmospheric pressure, the values of density, enthalpy, specific heat, sonic velocity, viscosity, thermal and electrical conductivities have been calculated for plasmas of PE and PTFE in the temperature interval 5 000 K-30 000 K. In hypothesis of LTE, equilibrium composition is calculated using the classical equations of thermodynamic, and transport coefficients are calculated using the Chapman-Enskog method. The accuracy of results is discussed in connection with the selection of the collision integrals of the different species

Composition and thermodynamic properties of ablated vapours of PMMA, PA6-6, PETP, POM and PE

“…The chemical equilibrium for the five plasmas formed in insulator vapours are shown in figures 1 to 5 in the temperature range 1000 K to 10 000 K. The results are in good agreement with other authors [2,[5][6][7] in the temperature range 5000-10 000 K, although these authors do not take the same chemical species into account, especially the polyatomic species.…”

“…For a better understanding of the interaction between the insulator wall and the arc, we need to know the composition and thermodynamic properties of the plasma formed in insulator vapours at low temperature. Many calculations resolving mass action laws [2,[5][6][7] and others using the Gibbs free energy minimization method [3,4] have already been made in the temperature range 5000-30 000 K. To complete these studies, we determine the composition below 5000 K. Previous experiments near the insulator wall during the interaction have shown that the temperature is low (< 8000 K) [8].…”

The influence of graphite on the composition and thermodynamic properties of plasma formed in ablated vapour of PMMA, PA6-6, PETP, POM and PE used in circuit-breakers

“…When the solid phase of carbon has not yet been formed the results are identical in the two cases. The concentrations between temperatures of 5000 and 10 000 K were given in our previous paper [15] and for temperatures higher than 10 000 K they have been given in various papers: PMMA in [1,6], PA6-6 in [1,5,6,11], PETP in [1,6], POM in [1,6] and PE in [1,4].…”

Thermodynamic properties calculation of air – water vapor mixtures thermal plasmas

“…Circuit breakers were the subject of several theoretical and experimental studies (André, et al, 2004;André, 1996;André, 1997, PP. 475-493;Abbaoui, et al, 1992;Andanson, et al, 1979;, PP. 1339-1359.…”