Wave-Mode Coordinate Analysis of 'L' Junction in LSS

Abstract

The propagation of structural disturbances through large space structures is of practical interest in the design and nondestructive evaluation of such large space systems. Many wave propagation analyses of large space structures must consider the reflection and transmission of waves at interconnecting junctions. Using the concepts of wave-mode coordinate analysis, a frequency domain study of wave propagation through an 'L' lattice junction is conducted. Each lattice member is modeled as a combined longitudinal rod and Timoshenko beam. The joint in the assembly is modeled as a rigid mass of negligible geometric extent with mass rotary inertia. In order to determine the input wave-mode vector, the joint coupling matrix is applied to a point along a lattice member which is subjected to externally applied sinusoidal loads. The input wave-mode vector contains a mathematical description of the waves generated by the applied sinusoidal loads. The joint coupling matrix for the rigid joint with mass and rotary inertia is presented and used to obtain the scattering matrix of the 'L' junction. The scattering matrix contains the reflection and transmission coefficients which the incoming waves will encounter as they enter the joint. Finally, the frequency response function of each Fourier transformed state variable of the transmitted waves is presented analytically.

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Document Details

Document Type
Technical Report
Publication Date
Mar 30, 1989
Accession Number
ADA211116

Entities

People

  • Derrick S. Webb
  • James H. Williams Jr.

Tags

Communities of Interest

  • C4I

DTIC Thesaurus Topics

  • Assembly
  • Coefficients
  • Composite Materials
  • Computer Programs
  • Couplings
  • Frequency
  • Frequency Response
  • Joints
  • Large Space Structures
  • Moment Of Inertia
  • Operating Systems
  • Reflection
  • Scattering
  • Time Domain
  • Timoshenko Beam
  • Two Dimensional
  • Wave Propagation

Fields of Study

  • Physics

Readers

  • Control Systems Engineering.
  • Electrical Engineering
  • Structural Dynamics.

Technology Areas

  • Space