On the influence of multi-quantum transitions on gas-dynamic parameters in the relaxation zone behind shock waves

Abstract

In this paper the influence of multi-quantum V T-exchanges on gas flow parameters in the relaxation zone behind a shock wave is studied. The set of equations of state-to-state vibrational-chemical kinetics coupled to the gas-dynamic equations is simulated numerically in the zero-order approximation of the Chapman—Enskog method. Rate coefficients of V T-transitions are calculated on the basis of Billing’s trajectory calculations. Distributions of fluid dynamic variables are obtained for the binary mixture N and N2 under various free stream conditions. Significant effect of multi-quantum transitions on the vibrational level populations and atom molar fractions is shown. The maximum error in temperature values calculated taking into account only single-quantum transitions is within 10–12%, and does not exceed 6–8% for the velocity. Refs 7. Figs 5.