Construction of an Anechoic Underwater Sound Measuring Tank

Abstract

The article describes a water basin with dimensions 7 m x 4 m x 4 m, which was constructed for measurements with water-borne sound. The walls of this basin are coated with absorbers effective in the frequency range from 5 to 70 kc. These broadband absorbers consist of a system of parallel, wedge-shaped rubber plates made up of three layers of rubber glued together. The center sheet is perforated with circular holes (diameter 4 mm, hole density 4%). There are three types of wedges differing in length (7, 15, and 20 cm) covering the frequency range from 5 to 70 kc. The reflection factor related to amplitude remains below 10% in this frequency range. The excellent acoustical properties of the anechoic measuring basin are confirmed by the very small standing wave ratio for all frequencies.

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Document Details

Document Type
Technical Report
Publication Date
Jan 29, 1965
Accession Number
AD0758095

Entities

People

  • E. Meyer
  • K. Tamm
  • W. Schilz

Organizations

  • Navy Underwater Sound Laboratory

Tags

Communities of Interest

  • Advanced Electronics
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Acoustic Impedance
  • Acoustic Properties
  • Acoustics
  • Attenuation
  • Frequency
  • Frequency Bands
  • Impedance
  • Materials
  • Measurement
  • Reflection
  • Repetition Rate
  • Resonant Frequency
  • Sound Pressure
  • Standing Wave Ratios
  • Standing Waves
  • Underwater Sound
  • Waves

Readers

  • Acoustical Oceanography.
  • Combustion and Flow Dynamics.
  • Structural Dynamics.