THE INTERACTION OF FINITE AMPLITUDE DEFLECTION AND STRETCHING WAVES IN ELASTIC MEMBRANES AND STRINGS

Abstract

Disturbances produced by the motion of a driver which is rigidly bonded to the edge of a plate are used to motivate parameter expansion techniques which when applied to the equations of finite elasticity, generate approximating equations which describe low frequency deflection and stretching waves travelling along stretched elastic plates and rods in the limit when bending forces are negligible compared with membrane forces. The structure of the boundary layer at the driven edge and shock layers, where the low frequency or filament approximations are locally invalid, are also discussed. The low frequency equations are used to discuss the interaction between progressing finite amplitude deflection and stretch waves in the limit when the stretch rate is small compared with the angular speed of the plate. The disturbance is locally that of a pure deflection simple wave whose amplitude and frequency are modulated by slow variations in the stretch. As the stretch increases the frequency increases while the amplitude decreases. The stretch wave is also modified by deflection of the plate: the speeds of wavelets carrying constant values of stretch are always less than their values in the pure stretch simple wave.

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Document Details

Document Type
Technical Report
Publication Date
May 01, 1968
Accession Number
AD0671840

Entities

People

  • David F. Parker
  • Eric Varley

Organizations

  • Lehigh University

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Boundary Layer
  • Computational Fluid Dynamics
  • Computational Science
  • Curvature
  • Differential Equations
  • Doppler Effect
  • Elastic Materials
  • Elastic Properties
  • Equations
  • Euler Equations
  • Fluid Mechanics
  • Frequency
  • Mechanics
  • Modulus Of Elasticity
  • New York
  • Stratified Fluids
  • Waves

Fields of Study

  • Mathematics

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Structural Dynamics.