A Study of Electron Collision Frequency in Air Mixtures and Turbulent Boundary

Abstract

The electron collision frequency is a critical parameter in determining the attenuation of electromagnetic signals transmitted through the plasma sheath surrounding advanced reentry vehicles. This study improves current methods of obtaining this parameter for multicomponent gas mixtures. A multicomponent collision frequency model is defined with temperature and species-dependent electron collision cross sections. A parametric study of collision frequency in a gaseous mixture of phenolic carbon and air is performed using this model, and the results are compared to calculations made using a constant cross-section, clean air model. A study of collision frequency and signal attenuation in turbulent boundary layers is performed using the multicomponent and constant cross-section models. This study shows that the multicomponent model can predict collisions frequencies in an ablation air mixture that are significantly different from those predicted by constant cross- section models.

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Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1972
Accession Number
AD0750553

Entities

People

  • Dennis W. Lankford

Organizations

  • Air Force Research Laboratory

Tags

Communities of Interest

  • Advanced Electronics
  • Weapons Technologies

DTIC Thesaurus Topics

  • Ablation
  • Ablative Materials
  • Air Force
  • Boundary Layer
  • Dielectric Permittivity
  • Elastic Scattering
  • Electron Density
  • Electrons
  • Free Electrons
  • Frequency
  • Literature Surveys
  • Magnetic Fields
  • Materials
  • Momentum Transfer
  • Particle Collisions
  • Reentry Vehicles
  • Scattering

Fields of Study

  • Physics

Readers

  • Computational Modeling and Simulation
  • Plasma Physics / Magnetohydrodynamics
  • Plasma Physics.

Technology Areas

  • Microelectronics