Shock-Tube Study of the Vibrational Relaxation of Nitrogen Using Vacuum-Ultraviolet Light Absorption
- 1 November 1967
- journal article
- research article
- Published by AIP Publishing in The Journal of Chemical Physics
- Vol. 47 (9), 3231-3240
- https://doi.org/10.1063/1.1712381
Abstract
The results of a shock‐tube study of the vibrational relaxation of nitrogen over the approximate temperature range 3000° to 9000°K are presented. Measurements were made using a vacuum‐ultraviolet light‐absorption technique at 1176 Å which monitored the rate of populating vibrational level v″≃10. The good agreement of the present results with earlier interferometric measurements demonstrates the validity of the assumption that the populations of vibrational levels from the ground state up to at least v″ = 10 relax via a continuous sequence of ``near'' Boltzmann distributions which are described by a single time‐dependent vibrational temperature. At temperatures in excess of about 5500°K, where no shock‐tube data have previously been reported, the results indicate that the local value of the characteristic vibrational relaxation time becomes increasingly dependent on the degree of vibrational excitation, such that it decreases within the relaxation region as equilibrium is approached.Keywords
This publication has 8 references indexed in Scilit:
- Vacuum-Ultraviolet Absorption of Shock-Heated Vibrationally Excited NitrogenThe Journal of Chemical Physics, 1967
- Flow Nonuniformity in Shock Tubes Operating at Maximum Test TimesPhysics of Fluids, 1966
- Shock-Tube Measurement of the Rate of Dissociation of NitrogenThe Journal of Chemical Physics, 1966
- Vibrational Relaxation of Diatomic MoleculesThe Journal of Chemical Physics, 1966
- Systematics of Vibrational RelaxationThe Journal of Chemical Physics, 1963
- Vibrational Energy Exchange between N2 and CO. The Vibrational Relaxation of NitrogenThe Journal of Chemical Physics, 1963
- Shock-Tube Study of the Kinetics of Nitric Oxide at High TemperaturesThe Journal of Chemical Physics, 1962
- Relaxation of an Isolated Ensemble of Harmonic OscillatorsThe Journal of Chemical Physics, 1960