Vibrational and electronic collisional-radiative model in CO2-N2-Ar mixtures for Mars entry problems

Abstract

To predict the nonequilibrium flows around a hypersonic vehicle entering the Martian atmosphere, the two-temperature collisional-radiative model “CoRaM-MARS” has been developed. The species CO2, CO, C2, CN, N2, NO, O2, C, N, O, Ar, CO+, C2+, CN+, N2+, NO+, O2+, C+, N+, O+, Ar+, and free electrons are taken into account. The model can therefore be used for conditions belonging to wide ranges of temperatures and pressures. The model is vibrationally specific on the ground electronic state of CO2, CO, C2, CN, N2, NO, and O2 and electronically specific for all species, with a total of almost 445 vibrational states and 1139 electronic states, respectively. Due to the high temperatures involved (∼40 000 K), a wide set of elementary processes is considered under electron and heavy particle impact reaching ∼106 forward and backward elementary processes. The model is implemented in a 1D Eulerian code simulating the shock crossing of the hypersonic flow in the conditions of the entry of the EXOMARS Schiaparelli module into the Martian atmosphere.