Investigation of Bias Errors in Laser Doppler Velocimeter Measurements.

Abstract

The problem of velocity bias laser Doppler Velocimeter (LDV) measurements made with counter type (burst) signal processors in turbulent flows was investigated. By using a signal processing technique which allowed velocity samples to be taken either randomly or at equal time intervals, the magnitude of the velocity bias was directly measured under various flow conditions. Using this technique, the validity of the one-dimensional velocity weighting correction of McLaughlin an Tiederman was investigated and found to be useful only at turbulence intensities below about 20 percent. Incomplete signal bias was also investigated and found to cause serious errors in unshifted LDV measurements. However, this bias may be virtually eliminated by frequency shifting. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1980
Accession Number
ADA097040

Entities

People

  • H. Doyle Thompson
  • Timothy C. Roesler
  • Warren H. Stevenson

Organizations

  • Purdue University

Tags

Communities of Interest

  • C4I

DTIC Thesaurus Topics

  • Acousto-Optic Modulators
  • Acquisition
  • Air Force
  • Computers
  • Data Acquisition
  • Data Analysis
  • Data Rate
  • Fluid Dynamics
  • Frequency Shift
  • Hydrodynamics
  • Laser Velocimeters
  • Measurement
  • Measuring Instruments
  • Ramjet Engines
  • Signal Generators
  • Signal Processing
  • Turbulent Flow

Fields of Study

  • Physics

Readers

  • Fluid Dynamics.
  • Phased Array Antenna Design.
  • Regression Analysis.

Technology Areas

  • Directed Energy