The Moving Thermoacoustic Array.

Abstract

In the optoacoustic sound generation process, a laser beam is directed at the water surface to produce a controlled local reaction which, in turn, generates sound waves. At low optical intensities, the reaction is a linear thermal expansion of the medium; hence the term thermoacoustic source. Extremely high Doppler shifts are achievable by scanning the laser beam across the water. A theoretical model of the thermoacoustic source was developed that uses a time domain approach. Special attention was paid to the sonic and transonic conditions where high pressure transients can be generated which may have practical applications. It was found that the thermoacoustic conversion process was most efficient when the optical energy was delivered as an impulse train. The efficiency upperbound for sea water was found to be limited, and therefore a more efficient process was sought. It is expected that processes that are significantly more efficent may be found at higher laser intensities. Keywords: Moving thermoacoustic source.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Jul 25, 1986
Accession Number
ADA174677

Entities

People

  • Illene J. Busch-vishniac
  • Nicholas P. Chotiros
  • Yves H. Berthelot

Organizations

  • University of Texas at Austin

Tags

Communities of Interest

  • Energy and Power Technologies
  • Sensors

DTIC Thesaurus Topics

  • Acoustic Signals
  • Acoustic Waves
  • Diffraction
  • Doppler Effect
  • Electromagnetic Radiation
  • Energy Conversion
  • Engineering
  • Frequency
  • Laser Beams
  • Lasers
  • Light (Electromagnetic Radiation)
  • Mach Number
  • Mechanical Engineering
  • Physical Properties
  • Repetition Rate
  • Solid State Lasers
  • Thermal Expansion

Fields of Study

  • Physics

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Medical Imaging.
  • Optical Physics and Photonics.

Technology Areas

  • Directed Energy