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.

The paper presents radiation models developed to investigate radiation in entry in Earth, Mars and Jupiter atmospheres. The capacity of ASTEROID computing code to simulate elementary radiative processes, calculate spectral and groups optical properties, and also solve simple radiative heat transfer problems is presented for Earth entry. The large number of radiative processes involved in the radiative flux is put forward. The contributions of the different radiative processes encountered in Mars entry are studied using the HTGR spectroscopic database. The validity of this database with respect to diatomic molecules systems and CO 2 infrared radiation is illustrated through experimental validations. The accuracy of statistical narrow-band model to predict radiative flux is illustrated for an afterbody. Finally recent improvements of the model developed for the calculation of radiative properties of high-temperature H 2 /He mixtures representative of Jupiter atmosphere is presented. The model takes into account the most important radiative processes.