Sound Speed and Attenuation in Multiphase Media

Abstract

One research goal developed from conducted shallow water (SW) acoustic transmission experiments in sandy-silty areas [1] revealed a nonlinear power law frequency-dependent attenuation at lower frequencies ( less than or equal to 1 kHz ) consistent with results reviewed in [2-5] and the observations by the ONR-HEP program. The Biot Theory [6] predicts that the sandy- sediment frequency-dependent attenuation should be quadratic, alpha( f ) =alpha( fo )( f / fo )(exp n) with n = 2; however the observed dependence was n = 1.8 plus/minus 0.2 . Thus the long-range goal was to develop a simplified theory of sediment attenuation [7] verified by measurements that could explain this dependence and be applied to ocean sediments.

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Document Details

Document Type
Technical Report
Publication Date
Sep 20, 2008
Accession Number
ADA532973

Entities

People

  • William M. Carey

Organizations

  • Boston University

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Attenuation
  • Conversion
  • Engineering
  • Fluids
  • Frequency
  • Internal Waves
  • Losses
  • Measurement
  • Mechanical Engineering
  • Secondary Waves
  • Sediments
  • Shallow Water
  • Surface Roughness
  • Transmission Loss
  • Water
  • Waves

Readers

  • Acoustical Oceanography.
  • Analytical Mechanics
  • Calculus or Mathematical Analysis