NONEQUILIBRIUM VIBRATIONAL KINETICS IN THE BOUNDARY-LAYER OF REENTERING BODIES

Nonequilibrium vibrational distributions of N-2 in the boundary layer surrounding a blunt body in hypersonic flow have been calculated by co upling the nonequilibrium vibrational kinetics, the dissociation and r ecombination processes, and the boundary-layer equations, The role of different energy exchange processes [vibration-vibration (V-V), vibrat ion-translation (V-T), and recombination-dissociation] in affecting vi brational kinetics has been studied by considering each process, Then the complete kinetics are taken into account, obtaining a global view of the interplay of the different microscopic processes, The model use d for the recombination/dissociation processes is such to selectively pump levels nu = 25 and 45 of the N-2 vibrational manifold, This vibra tional energy is then redistributed by V-V and V-T processes, As a res ult, strongly nonequilibrium vibrational distributions are obtained, d espite the thermalizing action of the V-T processes by nitrogen atoms.