State-resolved master equation analysis of thermochemical nonequilibrium of nitrogen

Abstract

Using a NASA database of state-to-state transition rates for N + N 2, master equation studies are performed for various nonequilibrium heat bath conditions. In these master equation studies, relaxation of the rotational and vibrational modes, time variation of chemical composition, reaction rate coefficients, and average rotational and vibrational energy losses due to dissociation are each considered in strong and weak nonequilibrium conditions. A system of master equations is coupled with one-dimensional flow equations to analyze the relaxation of N2 in post-normal shock flows. From the results of master equations and the post-normal shock calculations, it is recommended that the rotational nonequilibrium of N2 should be treated as a nonequilibrium mode in hypersonic re-entry calculations. © 2011 Elsevier B.V. All rights reserved.