T-Matrix Analysis of Acoustic Wave Scattering from Thin Elastic Shells.

Abstract

Progress has been made in the study of acoustic wave scattering by elastic obstacles immersed in water using the T-matrix approach. It is understood, that in problems of interest to the Navy, scattered field data is required for long, thin bodies of revolution whose wall thickness is very small compared to the wavelength of the incident wave but whose overall dimensions are comparable and often larger than the wavelength of the incident wave. This project was begun to precisely address such problems, taking into account and exploiting the thinness of the shell. We propose to use shell theory equations rather than the full elasticity equations in region I in order to avoid some of the complications. Shell theory reduces the partial differential equations in three coordinates to a higher order equation in two coordinates. All description of the displacement and stress fields is made with respect to a reference surface in the shell. Now, it is no longer necessary to invoke integral representations to describe the elastic field in this region. One extracts from the shell equations an expression for the impedance matrix of the shell which is then interfaced with the T-matrix approach for acoustic wave scattering problems.

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Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1981
Accession Number
ADA111980

Entities

People

  • V. K. Varadan
  • V. V. Varadan

Organizations

  • Ohio State University

Tags

Communities of Interest

  • Advanced Electronics
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Acoustic Waves
  • Bodies Of Revolution
  • Coordinate Systems
  • Differential Equations
  • Elastic Shells
  • Elastic Waves
  • Energy
  • Equations
  • Frequency
  • Helmholtz Equations
  • Impedance
  • Mechanical Impedance
  • Partial Differential Equations
  • Three Dimensional
  • Two Dimensional
  • Wave Equations
  • Waves

Fields of Study

  • Physics

Readers

  • Calculus or Mathematical Analysis
  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Structural Dynamics.