Testing the Accuracy of a Three-Dimensional Acoustic Coupled Mode Model

Abstract

The three-dimensional coupled mode sound propagation model of Chiu and Ehret (1990) is tested for its accuracy in modeling horizontal sound refraction. This test is achieved by comparing results generated by this model with exact analytic solutions to a parabolic approximation of the Helmholz Equation (Seigmann et al., 1990). Specifically, the acoustic wavefields associated with two cases of horizontally variable sound speed are considered. In Case I the sound speed varies only with azimuth, while in Case II there is radial and azimuth variation. The acoustic quantities used for the comparison include the modal modulation envelopes and transmission loss. Errors in the mode amplitude and phase are quantified and the significance of horizontal refraction is discussed.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1991
Accession Number
ADA247149

Entities

People

  • Hiroyuki Ogawa

Organizations

  • Naval Postgraduate School

Tags

Communities of Interest

  • C4I

DTIC Thesaurus Topics

  • Accuracy
  • Acoustic Waves
  • Acoustics
  • Amplitude
  • Classification
  • Differential Equations
  • Eigenvalues
  • Equations
  • Errors
  • Oceans
  • Refraction
  • Refractive Index
  • Security
  • Three Dimensional
  • Transmission Loss
  • Two Dimensional
  • Wave Equations

Fields of Study

  • Physics

Readers

  • Regression Analysis.
  • Wave Propagation and Nonlinear Chaotic Dynamics.