EFFECT OF H2O VAPOR ON THE VIBRATIONAL-RELAXATION IN HYPERSONIC WIND TUNNELS

This study concerns the development of numerical methods for the simul ation of flows in thermochemical nonequilibrium, Its purpose is to tak e into account some additional minor chemical species in the Navier-St okes solver CELHYO developed at ONERA, To solve the problem the time-d ependent set of equations that governs the flow of the major constitue nts (N-2, O-2, NO, N, O) and of the contaminants is used, The method i s applied to the effect of a contaminant such as H2O vapor on the vibr ational relaxation of N-2 and O-2 in two different hyperenthalpic wind tunnels: 1) the ONERA F4 hyperenthalpic wind tunnel and 2) the LBK of the DLR, The modifications of important flow parameters such as the t emperatures and the Mach number at the nozzle exits are presented.