LABORATORY MEASUREMENTS OF ELECTRON-DENSITY DISTRIBUTIONS IN NEAR WAKE

Recently attention has been focused on theoretical descriptions and experimental measurements of the effects of physical and chemical processes in wakes of high-velocity bodies. In particular, the electron-density distribution in the wake of typical re-entry vehicles has received much attention. In the present work, an attempt is made to obtain relative pointwise electron-density distributions in the near wake of models of typical re-entry configurations utilizing a slightly ionized hypersonic flow of a shock tunnel for that purpose. As the diagnostic instruments, Langmuir-type probes, arranged in the form of a rake, were used. It was found that the shock tunnel can-within limits'-be used to obtain information on the electron-density profiles in the near wake including the recirculation region, and that the relative electron density in the recirculation region for both blunt and slender bodies may vary over a range of three orders of magnitude under the test conditions of these experiments. © 1969 American Institute of Aeronautics and Astronautics, Inc., All rights reserved.