A WIND TUNNEL MEASUREMENT OF FLUCTUATIONS IN INFRARED EMISSION FROM A TURBULENT MIXING LAYER

Abstract

An investigation is reported of the fluctuating IR emission from hot air in a turbulent shear layer. A wind-tunnel experiment was conducted in which the free shear layer at the exit of a Mach 7 nozzle was observed with an AC radiometer. The radiating species was CO2 and the spectral response of the radiometer limited the observations to ists 2.7 micron band. The data were reduced both to broadband (25-25,000 cps) radiant emittance and to spectral density curves. Results obtained were compared with an analytical prediction of radiant emittance and good agreement has been obtained for one of the proposed models of turbulence intensity. The spectral density curves are peaked and the characteristic frequencies are partly consistent with those measured with hot wires in subsonic jets. (Author)

Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1964
Accession Number
AD0356438

Entities

People

  • Jacques A. F. Hill
  • James S. Draper
  • Lawrence D. Lorah

Tags

DTIC Thesaurus Topics

  • Agreements
  • Broadband
  • Emission
  • Emittance
  • Fluid Dynamics
  • Frequency
  • Hot Wire
  • Intensity
  • Measurement
  • Mixing
  • Observation
  • Radiometers
  • Turbulence
  • Turbulent Mixing
  • Wind Tunnels

Fields of Study

  • Physics

Readers

  • Atmospheric Remote Sensing.
  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Combustion and Flow Dynamics.