TRANSPORT-PROPERTIES OF NONEQUILIBRIUM GAS-MIXTURES

Transport properties of binary mixtures of diatomic gases in vibration al nonequilibrium are analyzed and the corresponding terms are establi shed. In order to solve the Boltzmann equation, a generalized Chapman- Enskog method is used, valid whatever the degree of nonequilibrium, co ntrarily to previous analyses in which only the extreme regimes were c onsidered, at weak or strong nonequilibrium, and generally for pure ga ses only. The transport coefficients, first written in terms of collis ion integrals, are finally expressed as functions of macroscopic quant ities, known or experimentally attainable, following Mason and Monchic k type approximations and with the harmonic-oscillator model. Finally, examples of calculations are given for N2-H-2 and O2-N2 Mixtures. Res ults are in good agreement with available experimental data. Compariso ns with approximate formulas, extensively used in the literature, show also that, at least for the investigated mixtures, the use of these f ormulas seems roughly justified.