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Knowledge of thermodynamic properties as well as parameters such as energy density and power flow is important for modeling thermal plasmas of fluoroalkylamine-air mixtures. In this paper, these thermodynamic properties of fluoroalkylamine-air mixture plasmas are calculated in a temperature range of 500 K to 20,000 K at atmospheric pressure and local thermodynamic equilibrium (LTE). The Gibbs free energy minimization method is used to determine the chemical equilibrium compositions of the plasmas that are needed to calculate the thermodynamic properties. These thermodynamic properties are then used to calculate the energy density and power flow of these plasmas. The variation of the energy density is related to the variations of the density and mass enthalpy. We notice that, this energy density increases with the percentage of air in the mixture for temperatures higher than 7000 K. The power flow, which depends also on density, enthalpy mass and sound speed, increases with the percentage of air in the same temperature range. Energy density and power flow results show that increasing air percentage in the mixture can be more interesting for damaging gaseous chemical species such as CF 2 , CO, HCN, and HF appearing at low temperatures with high concentrations.

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This paper concern the calculation of equilibrium composition of plasma mixture Air-Water vapor and copper vapor in temperatures range 1000K to 20000 K. The plasma is suposed to be in local thermodynamic equilibrium. We used Gibbs free energy minimization method to access the different numerical densities of chemical species as a function of temperature. This data are very important to calculate thermodynamic properties, transport coefficients and modeling electrical arc in circuit breakers. The result shows that the influence of metallic copper vapor is important on equilibrium composition of plasma. In particular the densities of electron in the plasma increase with the percentage of copper vapor for the temperature inferior to 17000K. The increasing of electron densities increase electrical conductivity of plasma and limit the performance of circuit breakers. Also the electrical neutrality is made mainly between electron (e-) and Cu + in low temperature (T < 12000K). We are studying in particular the evolution of the densities of the main chemical species created in this plasma as a function of pressure. We choose four values of pressure (1 atm, 5 atm, 10 atm and 15 atm). The results obtained shows an increasing of chemical densities with the pressure in the mixture in conformity at Dalton's Law. the increasing of the pressure in the plasma retard chemical reactions because it disadvantages the dislocations that constitute dissociation and ionization reactions in the plasma.

The transport coefficients of Air-PMMA mixtures thermal plasmas is important to estimate the performances of cutting of the electrical arc in this gas by a circuit breaker. In this paper, Air-PMMA mixtures thermal plasmas dynamical viscosity, thermal and electrical conductivities coefficients are calculated in a temperature range from 5000K to 30000K. The calculations are made by supposing thermodynamic equilibrium at pressure of 1 bar to 10 bar. The results of the calculations show the influence of the initial proportion of PMMA but also that of the pressure on the mixture plasma transport coefficients. As the efficiency of the breaking of the electric current by the circuit breaker depends closely on the thermal and electrical characteristics of the extinguishing medium, this extinguishing medium should have a high thermal conductivity and an electrical conductivity varying rapidly with temperature. The plasma of the mixture constituted by 80% of air and 20% of PMMA presents at first sight best characteristics for the breaking of electric current. It has the highest thermal conductivity peak among the plasmas of the mixtures studied.