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Electron – Air Molecule Collisions in Hypersonic Flows

  • Winifred M. Huo
  • Helmar T. Thümmel
Chapter
Part of the NATO ASI Series book series (ASIC, volume 482)

Abstract

At high vehicle velocity, the flow field surrounding a space vehicle becomes partially ionized, with the amount of ionization determined by the vehicle velocity. For a transatmospheric flight at an altitude of 80 km and a velocity of 10 km/sec, a maximum of 1% ionization is expected, whereas up to 30% of the atoms and molecules in the flow field will be ionized in a Mars return mission with a velocity of 12 – 17 km/sec. Even when the flow field is only slightly ionized, electron collisions still have an important role in determining the internal energy and state distribution of the atoms and molecules in the flow field. This in turn contributes to the flow characteristic and the amount of radiative heat load on the vehicle.

Keywords

Vibrational Level Vibrational Excitation Excitation Cross Section Hypersonic Flow Dissociative Recombination 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Kluwer Academic Publishers 1996

Authors and Affiliations

  • Winifred M. Huo
    • 1
  • Helmar T. Thümmel
    • 1
  1. 1.NASA Ames Research CenterMoffett FieldUSA

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