EXPERIMENTAL MEASUREMENTS OF TEMPERATURE AND RELAXATION TIMES BEHIND SHOCK WAVES

Abstract

By using a photomultiplier and cathode-ray oscillograph responsive only to changes in light signal, the sodium-line reversal technique has been adapted for time-resolved studies of temperature behind shock waves produced by a bursting diaphragm. A double-beam system has also been developed, which eliminates changes due to varying concentration of added metal, and interference filters can be used instead of a spectrograph. General agreement between calculated and observed temperatures is obtained, but both air and oxygen show a high-temperature region due to burning at the interface with the hydrogen driver gas. In nitrogen around 2400 K, a low temperature region close to the shock front may be attributed to a vibrational energy lag of the order of 100 microseconds, the sodium excitation following the effective vibrational temperature rather than the translational temperature of the nitrogen. In oxygen, evidence for a dissociation relaxation effect is obtained for shocks, giving temperatures of around 2500 K; this produces an abnormally high temperature near the front.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1959
Accession Number
AD0294131

Entities

People

  • A. G. Gaydon
  • I. Hurle

Organizations

  • AGARD

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies
  • Weapons Technologies

DTIC Thesaurus Topics

  • Carbon Dioxide
  • Chemical Reaction Properties
  • Chemical Reactions
  • Combustion
  • Computational Fluid Dynamics
  • Dissociation
  • Films
  • Fluid Dynamics
  • High Temperature
  • Ionization
  • Measurement
  • National Security
  • Nato
  • Radiation
  • Relaxation Time
  • Shock Tubes
  • Shock Waves

Fields of Study

  • Physics

Readers

  • Combustion Dynamics and Shock Wave Physics.
  • Image Processing and Computer Vision.
  • Thermal Physics or Thermal Science.