Advanced Models in Shock Waves

ABSTRACT

The paper presents three collisional-radiative models developed to investigate non-equilibrium chemistry and radiation in hypersonic shock tubes operating with different planetary atmospheres. An hybrid collisional-radiative model, employing the state-to-state kinetics of electronically excited states of molecules and the multi-temperature approximation for the vibrational degree of freedom is presented first, and applied to the numerical rebuilding of experimental shock tube emission spectra. Next, an hybrid collisional-radiative model for ionized air is presented. This model consider the state-tostate approach for electronic states of atoms and the multi-temperature model for the vibrational populations of diatomic molecules in their ground electronic state. A radiative transport equation is also solved to determine radiative source terms in the kinetic scheme and the enthalpy production due to radiation. The third model considers the state-to-state collisionalradiative model of Jupiter's atmosphere, self-consistently coupled with the Boltzmann equation for free electrons and the radiative transfer equation for the radiation transport in one-dimensional slab geometry.

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