FisMat2017 - Submission - View

Abstract's title: Vibrational kinetics of air species in space vehicle re-entry: the O + N2(v) and N + O2(v) collisions
Submitting author: Iole Armenise
Affiliation: CNR NANOTEC
Affiliation Address: Via Amendola 122/D, 70126 Bari
Country: Italy
Oral presentation/Poster (Author's request): Poster
Other authors and affiliations: Fabrizio Esposito (CNR NANOTEC)
Abstract

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 [1] and then used in a code which implements a state-to-state vibrational kinetics model [2]. 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 [3]. 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.

 

References

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