MODULATION TECHNIQUES FOR MEASUREMENTS IN LOW DENISTY HYPERSONIC WIND TUNNELS,

Abstract

A new technique for the measurement of small forces or other low level effects has been developed at the VKIFD low density wind tunnel. Measurement of forces as low as 10 micrograms appear feasible using ferroelectric transducers in conjuction with a low level tuned amplifier system and synchronous demodulator. This performance is made possible by periodically screening the flow on the model or even chopping the full flow of the wind tunnel by means of a mechanically actuated screen. Such modulation techniques, which result in considerable noise and drift reduction because of the narrow band width of a system using synchronous demodulation are of course widely used for the measurement of low level DC signals as well as detection of weak radiation, molecular beams, biological phenomena, etc. (Author)

Document Details

Document Type
Technical Report
Publication Date
Sep 25, 1964
Accession Number
AD0607382

Entities

People

  • J. J. Smolderen

Tags

DTIC Thesaurus Topics

  • Amplifiers
  • Biological Phenomena
  • Demodulation
  • Demodulators
  • Fluid Dynamics
  • Hypersonic Wind Tunnels
  • Low Density
  • Measurement
  • Modulation
  • Molecular Beams
  • Radiation
  • Tuned Amplifiers
  • Wind Tunnels

Fields of Study

  • Physics

Readers

  • Electrical Engineering
  • Fluid Dynamics.
  • Radio communications and signal processing.

Technology Areas

  • Hypersonics
  • Hypersonics - Hypersonic Flow