SHOCK TUBE PERFORMANCE OF A LANGMUIR PROBE SUITABLE FOR BALLISTIC RANGE APPLICATIONS,

Abstract

The shock tube performance of a Langmuir probe suitable for temporal electron density measurements in a large ballistic range is presented. The positively biased probe is designed to utilize a 0.001 in. wire held in tension as an electron collector in a 1000 K, for 3 torr turbulent wake which has a 0.004 in. mean free path. Preliminary measurements of the probe characteristics were made in a shock tube at an initial pressure of 0.02 torr and shock speed of 4.5 mm/microsec. Under these conditions, the mean free path of the test gas was 0.011 in., and the electron number density was 2.5 x 10 to the 11th power/cu cm. Because of the higher dynamic pressure in the shock tube, 0.005 in. wire was used and remained intact throughout the series of runs. Data taken over a range of probe voltages from low electron currents to saturation current were in satisfactory agreement with theoretical calculations based on equilibrium electron density.

Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1966
Accession Number
AD0800327

Entities

People

  • E. Locke
  • K. Plotkin

Tags

DTIC Thesaurus Topics

  • Dynamic Pressure
  • Electron Density
  • Electrons
  • Langmuir Probes
  • Mean Free Path
  • Measurement
  • Probes
  • Shock Tubes
  • Tubes

Fields of Study

  • Physics

Readers

  • Combustion and Flow Dynamics.
  • Plasma Physics.

Technology Areas

  • Microelectronics