VARIATION OF H2O AND CO2 CRYODEPOSIT REFLECTANCES WITH ANGLE OF INCIDENCE AND DEPOSIT THICKNESS

Abstract

Cryodeposits which form on the cryogenically cooled walls of a space simulation chamber can change the wall reflectance and thus alter the thermal balance of the test vehicle. In the study, H2O and CO2 cryodeposits of thicknesses up to 1.8 mm were formed on a 77K surface under vacuum. The spectral reflectances of these deposits were measured in situ with an integrating sphere for angles of incidence from 0 to 60 deg. At the smaller deposit thicknesses, the reflectance showed a strong dependence on both thickness and angle of incidence, whereas at larger thicknesses the dependence was less. A theoretical model developed for reflectance determination of absorbing and scattering media gives a good representation of the thickness dependence of water cryodeposit reflectance except at very small thicknesses where interference effects are known to occur.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1968
Accession Number
AD0674742

Entities

People

  • A. Matthew Smith
  • B. A. Seiber
  • Bobby E. Wood

Organizations

  • Arnold Engineering Development Complex

Tags

Communities of Interest

  • Advanced Electronics

DTIC Thesaurus Topics

  • Air Force
  • Angle Of Incidence
  • Carbon Dioxide
  • Chambers
  • Equations
  • Films
  • Flow Rate
  • Gas Flow
  • Ion Pumps
  • Measurement
  • Particle Size
  • Reflectance
  • Scattering
  • Space Simulation Chambers
  • Test Facilities
  • Test Vehicles
  • Thin Films

Fields of Study

  • Physics

Readers

  • Geotechnical Engineering.
  • Spectroscopy.

Technology Areas

  • Space
  • Space - Hall-Effect Thruster