The thermodynamic and transport properties of plasmas over a wide range of temperature and pressure are necessary to model the heat transfer and flow processes in plasma. In this study, the plasma composition is solved by simultaneous Saha equation, Dalton's partial pressure law and charge quasi-neutral equation. The thermodynamic properties of plasma computation are based on the kinetic theory for ideal gas. While the calculation of transport properties is based on the solution of Boltzmann’s equation by the Chapman-Enskog method. The thermodynamic and transport properties of argon-nitrogen plasma at pressures of 0.1, 1.0 and 10.0 atm, electron temperatures ranging from 300 to 30000 K, and non-local thermodynamic equilibrium (NLTE), where the electron temperature is not equal to the temperature of heavy particles,, are investigated by using the above method. The results show that the value of non-equilibrium parameter has a great influence on the properties of the argon-nitrogen mixture. With the increase of non-equilibrium parameter, the dissociation reaction requires a higher electron temperature, which leads the dissociation peak to shift to a higher electron temperature. The ionization and dissociation reaction will enter into the high temperature region due to the increase in pressure. This change will affect the peak position and value of the specific heat, viscosity, thermal conductivity and electrical conductivity of plasma. In addition, since the electronic translational thermal conductivity and electrical conductivity mainly depend on the electron number density, when non-equilibrium parameter and pressure increase, the electron number density will increase at high electron temperature, thus improving the electronic translational thermal conductivity and electrical conductivity. Under the condition of local thermodynamic equilibrium, the transport properties of argon-nitrogen plasma obtained by calculation are in good agreement with previously reported data.
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