NOZZLE FLOWS WITH COUPLED VIBRATIONAL AND DISSOCIATIONAL NONEQUILIBRIUM,

Abstract

It was assumed that the vibrational state of the gas may be represented by a single vibrational temperature and that the effect of vibrational nonequilibrium on rates of dissociation may be taken into account by the introduction of a parameter which has the dimensions of temperature and which gives a higher probability for dissociation from higher vibrational energy levels. The dependence of this parameter on translational temperature is derived. However, in the calculations, an averaged constant value of this parameter is used as a simplification. The effect of dissociational nonequilibrium on vibrational relaxation is to modify the classical Landau-Teller equation by additional terms which take into account the average energy lost or gained due to dissociation and recombination. A qualitative study of the effects of the atom-molecule exchange reaction and relaxation from a higher to lower vibrationally excited state on the vibrational relaxation is carried out by shortening the vibrational relaxation times from those measured behind normal shocks. The analysis was successfully applied to predict the hypersonic nozzle test-section conditions for a newly developed UTIAS self-calibrating catalytic probe for measuring local atom concentrations in a dissociating oxygen flow. (Author)

Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1967
Accession Number
AD0657944

Entities

People

  • Duvvuri Tirumalesa

Organizations

  • University of Toronto

Tags

DTIC Thesaurus Topics

  • Dissociation
  • Energy Levels
  • Equations
  • Exchange Reactions
  • Hypersonic Nozzles
  • Molecules
  • Nozzles
  • Probability
  • Relaxation Time
  • Vibrational Relaxation

Fields of Study

  • Physics

Readers

  • Combustion science or combustion engineering.
  • Fluid Dynamics.
  • Quantum spin resonance or Electron Paramagnetic Resonance spectroscopy.

Technology Areas

  • Hypersonics
  • Hypersonics - Hypersonic Flight
  • Hypersonics - Hypersonic Flow