Advanced models for vibrational–chemical coupling in multi-temperature flows

Abstract

In this paper, self-consistent models for coupled vibrational relaxation and dissociation in multi-temperature gas mixture flows are proposed on the basis of the kinetic theory methods. The Treanor–Marrone dissociation model is generalized taking into account the dependence of model parameter on the vibrational state. Multi-temperature dissociation rate coefficients are calculated on the basis of the improved Treanor–Marrone model using the Boltzmann and Treanor vibrational distributions; comparison with traditional models shows a significant difference in the dissociation rate coefficients for high temperatures. Generalization of the well known Landau–Teller model overcoming limitations of the original model is proposed. The developed models are validated against experimental data and assessed in non-equilibrium shock heated flows of O2/O and N2/N mixtures. It is shown that the proposed models provide a good accuracy in the wide range of flow conditions while being simple and computationally efficient.