Simulation of Radiative Transfer in Nonequilibrium Plasmas Containing N and O Species Based on the Approximate Collision-Radiative Method

An approximate collision-radiative method is developed to calculate energy level populations of atoms and applied to simulate radiative transfer in a shock layer.Considering nonequilibrium plasmas with the electronic temperature below 20000 K,we introduce correction factors to the Saha–Boltzmann equation and simplify the master equation of the full collision-radiative model.Based on the method,the error of heat flux is smaller than 5%in a two-cell problem and smaller than 7%in the Stardust re-entry flow field compared with the correlated-k method.Furthermore,almost a factor of 2 is obtained in the improvement of computational efficiency compared with the nonequilibrium air radiation(NEQAIR)code.The results show that the present method is reliable and efficient.