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 consistent with results reviewed in [2,3] and the observations by the ONR-HEP program. The Biot Theory [4] predicts that sandy sediment attenuation should have a quadratic dependence, however the nonlinear dependence observed was closer to a 1.8 power law most likely due to modal effects. Thus one long-range goal is to develop a simplified theory of sediment attenuation [5] verified by measurements that can be applied to ocean sediments. A second long-range goal is to better understand that acoustical behavior of individual bubbles and bubbly assemblages in water and water-filled sediments. The focus is on attenuation, dispersion, and bubble response near and about the resonance frequency.

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Document Details

Document Type
Technical Report
Publication Date
Sep 30, 2006
Accession Number
ADA613566

Entities

People

  • Ronald A. Roy
  • William M. Carey

Organizations

  • Boston University

Tags

Communities of Interest

  • Autonomy
  • Energy and Power Technologies
  • Sensors
  • Space

DTIC Thesaurus Topics

  • Acoustic Properties
  • Acoustics
  • Arrays
  • Attenuation
  • Autonomous Vehicles
  • Engineering
  • Frequency
  • Losses
  • Measurement
  • Mechanical Engineering
  • Power Amplifiers
  • Shallow Water
  • Signal Processing
  • Small Ships
  • Towed Arrays
  • Transmission Loss
  • Vehicles

Readers

  • Acoustical Oceanography.
  • Theoretical Analysis.