Nonequilibrium vibration-dissociation properties of diatomic molecule behind shock waves

The vibration and dissociation processes of Diatomic Molecule are presented. The energy levels of gas are excited with chemical reactions such as dissociation in which several components are generated with the chemical reacting flow, and due to different reactions with different relaxation times, the gas is in the thermochemical nonequilibrium state. The distribution of vibrational levels has an obvious impact on chemical reactions such as dissociation and characters of flow fields. The feature of vibrational levels distribution from the structure of molecule and the energy transport is significant to understand the nonequilibrium processes. An empirical or semiempirical model of nonequlibirium vibrational relaxation through some reasonable analyses is used to solve the vibration-dissociation problems. It is found that the relative population density difference between the vibrational levels and molecule-atom collisions have impact on vibration excitation and dissociation.