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.