The Development of a Diode Laser Doppler Velocimeter for Boundary Layer Measurements Under Ice: A Feasibility Investigation.

Abstract

Measurements of the turbulent fluxes of momentum, heat, and salinity in the oceanic boundary layer are difficult to obtain, as both a stable platform and high-resolution instrumentation are required. The overall objective of the present investigation, was to develop a boundary layer instrumentation system capable of measuring turbulent fluxes in the marginal ice zone environment. This investigation focuses on a feasibility study toward development of a diode laser Doppler velocimeter (DLDV) to be used as the velocity sensor for a high-resolution velocity/temperature/conductivity cluster, with a spatial resolution of 1 to 2 cm. Phase I findings show very promising results for the DLDV in laboratory environments. Measurements in a pipe flow facility demonstrated very distinctive Doppler burst signals, with more than adequate signal-to-noise ratio, even in clean tap water passed through a 10 micrometer filter. Excellent burst density was observed when a small quantity of Puget Sound water was added to the tap water. For all practical purposes, the performance of the DLDV is at least as good as that of a well-established LDV system using a helium-neon laser as the light source.

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Document Details

Document Type
Technical Report
Publication Date
May 01, 1984
Accession Number
ADA145076

Entities

People

  • H. T. Liu
  • J. C. Schedvin

Tags

Communities of Interest

  • Advanced Electronics
  • Energy and Power Technologies
  • Materials and Manufacturing Processes
  • Sensors

DTIC Thesaurus Topics

  • Boundary Layer
  • Doppler Effect
  • Electronics Laboratories
  • Gas Lasers
  • Helium Neon Lasers
  • High Resolution
  • Laser Beams
  • Laser Diodes
  • Lasers
  • Light Sources
  • Measurement
  • Measuring Instruments
  • Optical Correlators
  • Scattering
  • Semiconductor Lasers
  • Semiconductors
  • Test Facilities

Fields of Study

  • Physics

Readers

  • Coastal Oceanography
  • Fluid Dynamics.
  • Optical Physics and Photonics.

Technology Areas

  • Directed Energy