EPJ Web of Conferences 84, 06005 (2015)
https://doi.org/10.1051/epjconf/20158406005

Dissociative recombination in reactive flows related to planetary atmospheric entries

¹ CORIA, UMR CNRS 6614, Université de Rouen, Site Universitaire du Madrillet, BP. 12, 76801 Saint-Etienne du Rouvray, France
² Aix-Marseille Université, CNRS, IUSTI UMR 7343, 13013 Marseille, France

^a e-mail: arnaud.bultel@coria.fr
^b e-mail: julien.annaloro@coria.fr
^c e-mail: marie-claude.druguet@univ-amu.fr; 5 rue Enrico Fermi

Published online: 29 January 2015

Abstract

The Dissociative Recombination (DR) processes play a significant role in plasma chemistry. This article illustrates this role from the modeling point of view in the case of reactive flows related to atmospheric entry plasmas. Two situations are investigated, for which the studied plasma is nitrogen. The first configuration corresponds to the relaxation process behind a strong shock wave moving at high Mach number in a shock tube, the second one to the recombination taking place in an expanding plasma flowing in a diverging nozzle. In both cases, the collisional-radiative model CoRaM-N₂, involving N₂, N, N₂⁺, N⁺ and electrons, is implemented in an Eulerian 1D code able to compute the aerodynamic fields; calculations are performed in standard conditions. We show that, according to the rate coefficients used for the DR processes, the population density of the charged species especially N₂⁺ is strongly modified only for the post-shock flow.