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In the present study, a theoretical model of state-resolved transport properties in electronically excited atomic species developed earlier is applied to argon and carbon atomic species. It is shown that for Ar and C, similarly to the case of atomic nitrogen and oxygen, the Slater-like models can be applied to calculate diameters of electronically excited atoms. Using the Slater-like model it is shown that for half-filled N ( 2 p x 1 p y 1 p z 1 ) and full-filled Ar ( 3 p x 2 p y 2 p z 2 ) electronic shells the growth of atomic radius goes slowly compared to C ( 2 p x 1 p y 1 ) and O ( 2 p x 2 p y 1 p z 1 ). The effect of collision diameters on the transport properties of Ar and C is evaluated. The influence of accounted number of electronic levels on the transport coefficients is examined for the case of Boltzmann distributions over electronic energy levels. It is emphasized that in the temperature range 1000–14000 K, for Boltzmann-like distributions over electronic states the number of accounted electronic levels do not influence the transport coefficients. Contrary to this, for higher temperatures T > 14000 K this effect becomes of importance, especially for argon. [ABSTRACT FROM AUTHOR]

In the present work we evaluate the accuracy of the Eucken formula and Stokes' viscosity relation in high temperature non-equilibrium air species with electronic excitation. The thermal conductivity coefficient calculated using the exact kinetic theory methods is compared with that obtained applying approximate formulas in the temperature range 200 -- 20000 K. A modification of the Eucken formula providing a good agreement with exact calculations is proposed. It is shown that the Stokes viscosity relation is not valid in electronically excited monoatomic gases at temperatures higher than 2000 K. [ABSTRACT FROM AUTHOR]

In the present paper, a strongly non-equilibrium one-dimensional steady-state flow behind the plane shock wave is studied. We consider a high-temperature chemically reacting five-component ionized mixture of nitrogen species (N2/N+2/N/N+/e-) taking into account electronic degrees of freedom in N and N+ (170 and 625 electronic energy levels respectively), and electronic-rotational-vibrational modes in N2 and N+2(5 and 7 electronic terms). Non-equilibrium reactions of ionization, dissociation, recombination and charge-transfer are included to the kinetic scheme. The system of governing equations is written under the assumption that translation and internal energy relaxation is fast whereas chemical reactions and ionization proceed on the macroscopic gas-dynamics time-scale. The developed model is applied to simulate the flow behind a plane shock wave under initial conditions characteristic for the spacecraft re-entry from an interplanetary flight (Hermes and Fire II experiments). Fluid-dynamic parameters behind the shock wave as well as transport coefficients and the heat flux are calculated for the (N2/N+2/N/N+/e-) mixture. The effect of electronic excitation on kinetics, dynamics and heat transfer is analyzed. Whereas the contribution of electronic degrees of freedom to the flow macroparameters is negligible, their influence on the heat flux is found to be important under conditions of Hermes re-entry. [ABSTRACT FROM AUTHOR]

Chemically non-equilibrium neutral gas mixture flows of N2/N and O2/O with electronic excitation are studied. The one-temperature model of transport properties taking into account electronic states of both molecules and atoms is developed. The generalized Chapman-Enskog method is applied to derive the closed set of governing equations and to evaluate the transport terms. The transport coefficients of thermal conductivity, diffusion and thermal diffusion, shear and bulk viscosity, as well as the Prandtl number are calculated in the temperature range 500-50000 K for various mixture compositions. Contribution of the electronic degrees of freedom to the transport properties is found to be important, especially for atomic species. [ABSTRACT FROM AUTHOR]