STUDY OF INFRARED EMISSION FROM HYPERSONIC AIR FLOWS

Abstract

Research is being conducted to formulate a comprehensive picture of the IR radiation from reentry bodies. The program is divided into: (1) the experimental determination of the radiative properties of the optically active gaseous species, and (2) the analysis of the blunt-body flow field, in which the finite-rate chemistry of the air is coupled with the aerodynamics of the flow. The final analysis of the nitrogen first-positive band spectrum has been completed. The measured intensities are lower by a factor of 5 than those reported for measurements in shock-heated air. The nonequilibrium radiation from this N2(1+) system, arising from the finite rate of electronic excitation has been studied. A machine program generated the spectra of radiating species from the known spectroscopic constants and the experimentally determined transition probabilities. Several re-entry flow calculations were completed, and a nonequilibrium scaling criterion investigated. Computations are discussed and the scaling criterion is valid for the IRBM (15,000 fps) and ICBM (23,000 fps) conditions.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1962
Accession Number
AD0273865

Entities

People

  • Paul V. Marrone
  • Walter H. Wurster

Organizations

  • Calspan

Tags

Communities of Interest

  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Accuracy
  • Aeronautical Laboratories
  • Air Flow
  • Altitude
  • Bodies
  • Chemical Reaction Properties
  • Chemical Reactions
  • Chemistry
  • Dissociation
  • Fluid Dynamics
  • Free Flight
  • New York
  • Nonequilibrium Flow
  • Pressure Distribution
  • Pressure Measurement
  • Stagnation Point
  • Thermodynamic Properties

Fields of Study

  • Physics

Readers

  • Combustion science or combustion engineering.
  • Fluid Mechanics and Fluid Dynamics.
  • Molecular Photonics/Laser Physics

Technology Areas

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