GAS-SURFACE INTERACTIONS.

Abstract

A method has been developed for measuring the transfer of energy from a molecular beam to a surface. The method makes use of temperature sensitive Y-cut quartz crystals. A crystal was placed in the beam and the energy transferred to its plating was determined by changes in its oscillating frequency. Crystals having a fundamental frequency of 10 Mc/sec were used and an energy transfer rate of 50 microwatts could be detected. Probe for Measuring Energy Transfer Between a Satellite and the Upper Atmosphere, by D. McKeown, M. G. Fox, and J. Kay: A probe has been developed to measure energy transfer between a satellite surface and the upper atmosphere. Energy transfer is detected by the frequency change of a temperature-sensitive quartz crystal located in the nose of the probe. Transfer rates down to 15 micro W/ sq cm can be measured. Data provided by the probe can be used to determine the accommodation coefficients of surfaces, and periodic variations in the atmospheric density. Results of a satellite flight show that the probe will operate at altitudes up to 500 km where the atmospheric density is still great enough to produce measurable heating.

Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1965
Accession Number
AD0623980

Entities

People

  • D. Mckeown
  • H. R. Poppa
  • J. Kay
  • M. G. Fox

Organizations

  • General Dynamics

Tags

Communities of Interest

  • Space

DTIC Thesaurus Topics

  • Altitude
  • Artificial Satellites
  • Atmospheres
  • Atmospheric Density
  • Energy
  • Energy Transfer
  • Frequency
  • Gas Surface Interactions
  • Molecular Beams
  • Periodic Variations

Fields of Study

  • Environmental science
  • Physics

Readers

  • Aerospace Propulsion Engineering.
  • Molecular Photonics/Laser Physics
  • Thermal Physics or Thermal Science.

Technology Areas

  • Space
  • Space - Hall-Effect Thruster