During the re-entry of a space vehicle in the Earth atmosphere a plasma is formed around it. It has been demonstrated that the vibrational non-equilibrium in the hypersonic boundary layer around the nose is successfully studied by means of the state-to-state vibrational kinetics model. The present model includes vibrational-translational, vibrational-vibrational, dissociation-recombination processes and exchange reactions.
In this work the formation of NO by the reactions
O + N2(v) <--> NO(w) + N
N + O2(v) <--> NO(w) + O
and the dissociation processes
O + N2(v) -> 2N + O
N + O2(v) -> 2O + N
are investigated. The rate coefficients, calculated by means of the quasiclassical trajectory method, are analyzed  and then used in a code which implements a state-to-state vibrational kinetics model . The vibrational non-equilibrium that arises under particular conditions, through the evolution of the system from an initial state to a final one, is investigated. Results obtained in a N2/N/O2/O/NO mixture to simulate air, either in a zero-dimensional or in a one-dimensional solver, are presented.
The one-dimensional code solves an hypersonic boundary layer . It analyses a viscous, chemically reacting flow and provides the species mass fractions, the molecular species vibrational distributions and the temperature along the coordinate normal to the reentering vehicle surface.
1 - F.Esposito, I.Armenise, "Reactive, inelastic and dissociation processes in collisions of atomic oxygen with molecular nitrogen", submitted for publication on The Journal of Physical Chemistry
2 - I.Armenise, F.Esposito, "N2, O2, NO state-to-state vibrational kinetics in hypersonic boundary layers: The problem of rescaling rate coefficients to uniform vibrational ladders", Chemical Physics, Vol.446, 2015, pp.30-46, DOI:10.1016/j.chemphys.2014.11.004
3 - I.Armenise, M.Capitelli, "State to state vibrational kinetics in the boundary layer of entering body in earth atmosphere: particle distributions and chemical kinetics", Plasma Sources Science & Technology, Vol.14, No.2, 2005, pp. S9-S17, DOI:10.1088/0963-0252/14/2/S02