FisMat2017 - Submission - View

Abstract's title: e- + CO2 collisions: vibraional kinetics and eedf
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:
Abstract

Abstract

A theoretical model, as well as its numerical implementation, developed to investigate the state-to-state vibrational kinetics of a triatomic CO2 molecule will be presented. The CO2 molecule is approximated to a molecule with three not independent vibrational modes: the symmetric stretching mode, the two degenerated bending modes treated as a unique one, the asymmetric stretching mode [1]. As a consequence, the CO2 vibrational state is v=(v1,v2,v3), with v1, v2 and v3 the vibrational quantum numbers of the three different modes. The vibrational kinetics traces the evolution of the vibrational distribution due to different kinetic proceses like the vibrational-translational VTm transitions in each mode, the intra-mode vibrational transitions VV3, the inter-mode VV1-2-3 exchanges within CO2 molecule, the inter-mode VV1-2-CO and VV2-CO exchanges between molecules of different chemical species, the dissociation-recombination reactions [2-4].

The rates coefficients of the kinetic processes are calculated on the basis of the SSH theory.

In this framework, to solve the vibrational kinetics of CO2, the electron-CO2 collisions are considered in the same way as the previous processes, however their rate coefficients comes out from the solution of the Boltzmann equation which provides the electron energy distribution function [5].

Results obtained either in a zerodimensional model or in a monodimensional one will be presented.

 

References

1- I. Armenise, E.V. Kustova, "State-to-state models for CO2 molecules: From the theory to an application to hypersonic boundary layers", Chemical Physics, Vol.415, 2013, pp.269-281

2- E.V.Kustova, E.A.Nagnibeda, "On a correct description of a multi-temperature dissociating CO2 flow",  Chem. Phys., Vol.321, 2006, pp.293-310

3- E.V. Kustova, E.A. Nagnibeda, "Kinetic model for multi-temperature flows of reacting carbon dioxide mixture",  Chemical Physics, Vol.398, 2012, pp.111-117

4- I.Armenise and E.Kustova, "Sensitivity of Heat Fluxes in Hypersonic CO2 Flows to the State-to-state Kinetic Schemes", in 30th International Symposium on Rarefied Gas Dynamics: RGD 30, A.Ketsdever and H.Struchtrup Ed.s, AIP Conference Proceedings, Vol. 1786, 2016, pp.150011-1-8, doi:10.1063/1.4967652; ISBN: 978-0-7354-1448-8

5- I.Armenise, "Excitation of the lowest CO2 vibrational states by electrons in hypersonic boundary layers", Chemical Physics, Vol.491, 2017, pp. 11-24