An asymptotic theory of the sound dispersion in a binary mixture of gases

The sound propagation in a binary mixture of multiatomic non-relaxing gases is considered using Burnett's equations (for the case of rapid exchanges of the internal and translational energies of the molecules). Asymptotic expressions (for small Knudsen numbers) are obtained for the absorption and dispersion coefficients, which are expressed in terms of the Navier–Stokes and the Navier–Stokes and the Burnett transport coefficients respectively. “Working” expressions of different levels of accuracy for these coefficients are known for the case of a binary mixture of monatomic gases. For this case, the results obtained are compared with known ones and the drawbacks and errors of previous papers are pointed out.