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A detailed analysis of the processes of charged and neutral species formation in N 2 -O 2 -Ar system behind strong shock waves is conducted on the basis of an extended thermally non-equilibrium kinetic model with careful allowance of reactions with electronically excited atoms and molecules and vibration-electron-chemistry coupling. The model is validated against experimental data such as measurements of electron number density behind the strong shock wave front, temporal profile of O 2 vibrational temperature, temporal evolution of NO(γ ) radiation intensity in the post-shock region and values of time instants at which maximum quantities of radiation intensity of N 2 (1+) and N + 2 (1−) bands are achieved. It is demonstrated that the model without the allowance of processes involving electronically excited atoms and molecules overestimates the concentrations of both charged and neutral species. For electron and NO concentrations the overestimation can come up to a factor of 2. The computations also indicate the existence of a strong vibration-electron-chemistry coupling in the air plasma produced by the strong shock wave. Only the model, which takes into account such an interaction, makes it possible to properly predict the variation of gas dynamic parameters and species concentrations in the post-shock region.

A new kinetic thermal nonequilibrium model for air plasma, considering vibrations of , and molecules in both the ground and electronically excited states in a state-to-state approach, was developed. The model treats in a consistent way the coupling of vibrational–electronic excitation of molecules and plasma chemical reactions as well as thermal nonequilibrium between translational degrees of freedom of electrons and heavy particles. The model was validated against the values of the radiation intensity of the and bands measured in the shock-tube experiments in an – mixture at shock wave speeds up to . Numerical analysis of thermally nonequilibrium processes in shock wave air plasma using the developed state-to-state model was conducted. It was shown that behind the shock front, a non-Boltzmann distribution over vibrational levels of , and molecules in both the ground and electronically excited states forms, but at the same time low vibration levels of these molecules are still populated in line with the local Boltzmann distribution with its own vibrational temperature. However, at extremely high shock wave velocities () disruption of the Boltzmann distribution of and molecules starts from vibrational levels with quantum numbers , so it is worth using the state-to-state consideration in such cases.

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