POPULATION DISTRIBUTIONS DURING VIBRATIONAL RELAXATION OF DIATOMIC GASES,
Abstract
A master equation analysis for the vibrational relaxation of a diatomic gas is presented, including the effects of near-resonance exchange of vibrational energy between colliding oscillators. It is found that the mechanism of rapid near-resonance exchange of vibrational energy among the diatomic species tends to maintain a quasi-steady state vibrational population distribution during the relaxation of a pure gas. The specific functional form of this quasi-steady state distribution is determined from a perturbation analysis of the master equation. A detailed analyses is also given of the relaxation equations for the case of equi-distant vibrational energy level spacing. It is found that when the diatomic gas is diluted by an inert to the extent that oscillator-oscillator exchange collisions no longer influence relaxation, the vibrational population distribution can depart markedly from the Boltzmann form. Whenever exchange collisions predominate, however, it is found that a near-Boltzmann distribution is preserved, regardless of the form of the vibration-translation transition probabilities, and the energy relaxation equation does not differ greatly from the Landau-Teller result. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1966
- Accession Number
- AD0634437
Entities
People
- J. W. Rich
- R. G. Rehm
Organizations
- Calspan