On the non-equilibrium kinetics and heat transfer in nozzle flows

In this paper the influence of different vibrational distributions on heat transfer and diffusion in expanding nozzle flows is studied. Non-equilibrium, flows of N-2/N and 0(2)/0 mixtures with dissociation, recombination and excitation of vibrational levels are considered. Vibrational distributions, gas dynamic parameters as well as the transport coefficients and total energy flux are computed along the nozzle axis using four approaches of the transport kinetic theory: a rigorous state-to-state approximation, quasi-stationary two-temperature models for harmonic and anharmonic oscillators and a thermal equilibrium one-temperature model. A comparison of vibrational distributions and transport properties obtained in different approaches is presented. (C) 2002 Published by Elsevier Science B.V.