ERC Model for Prediction of Molecular Bands Radiation for Stardust Entry Conditions

Abstract

Mathematical modeling of Stardust flight data is performed with the use of computer platform NERAT(2D)+ASTEROID. This computer platform intended for solving full system of radiative gasdynamic equations of viscous, heat conductive, physically and chemically nonequilibrium gas, as well as the radiation heat transfer equations in 2D geometries. Two models of physical kinetic are used. The first model is based on the multi-temperature approach with consideration of the translational temperature, vibrational temperatures of N2, O2 and NO, as well as the electronic temperature. Processes of non-equilibrium dissociation are taken into account by means of the classical model of Treanor and Marrone. The second model is the radiative-collisional (RC) model which is formulated for electronic states of diatomic molecules N2, N2 and NO. Kinetic equations of the RC-model are considered in detail. The problems of the providing the RC-model by constant rates for excitation and deactivation of separately considered electronic states at collision of diatomic molecules with electrons and heavy particles are discussed, as well as kinetic constants for spontaneous photon emission and associative recombination reactions. Obtained calculation data are compared with calculation data of other authors. Results of systematic calculations of radiative gas dynamics of Stardust are presented in the form of atlas of calculated data. Each trajectory points is characterized by the following data: two-dimensional fields of velocity, pressure, density, translational and vibrational temperatures; axial distributions of translational and vibrational temperatures, mass fractions, one-sided integral radiation heat fluxes along stagnation line, spectral distributions of radiation heat flux density as well as cumulative function.