Electron-vibration energy exchange models in nitrogen-containing plasma flows.

The physics of vibrational kinetics in nitrogen-containing plasma produced by collisions with electrons is studied on the basis of recently derived cross sections and rate coefficients for the resonant vibrational-excitation by electron-impact. The temporal relaxation of the vibrational energy and of the vibrational distribution function is analyzed in a state-to-state approach. The electron and vibrational temperatures are varied in the range [0-50,000] K. Conclusions are drawn with respect to the derivation of reduced models and to the accuracy of a relaxation time formalism. An analytical fit of the vibrational relaxation time is given.