Hamilton's Principle and the Equations of Motion of an Elastic Shell with and without Fluid Loading

Abstract

It has proven quite difficult to employ exact elastodynamic theory to describe the behavior of elastic vibrations on arbitrary bounded shells. In addition, exact theories preclude direct interpretation of Particular features observed due to the excitation of elastic shell surfaces. A rather interesting approach to describe surface vibrations may be obtained by constructing a Hamiltonian in some approximate form that assumes some correlation of motion of the outer and inner shell surface. The class of theories that allow for this approach are referred to in applied mechanics and shell theories. The interesting feature of this Hamiltonian approach is that one can add various physical mechanisms to the Hamiltonian such as extensional motion, rotary inertia, shear distortion, fluid loading, etc., and thereby study the individual contributions to resonance patterns white adding physical insight to the fundamental processes that occur on shell surfaces. We develop shell theories in this manner and examine various contributions via Hamilton's principle. We believe that fluid loading has by and large not been treated adequately in the past, and we place particular emphasis on the treatment of that contribution to this work. Acoustic scattering, shallow water, waveguide propagation.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1992
Accession Number
ADA256396

Entities

People

  • Cleon E. Dean
  • Michael F. Werby

Organizations

  • United States Naval Research Laboratory

Tags

DTIC Thesaurus Topics

  • Acoustic Impedance
  • Acoustic Scattering
  • Applied Mathematics
  • Applied Mechanics
  • Differential Equations
  • Elastic Shells
  • Energy
  • Equations
  • Equations Of Motion
  • Kinetic Energy
  • Mathematics
  • Mechanics
  • Modulus Of Elasticity
  • Potential Energy
  • Scattering
  • Stresses
  • Three Dimensional

Fields of Study

  • Physics

Readers

  • Calculus or Mathematical Analysis
  • Structural Dynamics.
  • Systems Analysis and Design