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Journal of Nondestructive Evaluation

, Volume 11, Issue 3–4, pp 175–184 | Cite as

A comparison of exact first order and spring boundary conditions for scattering by thin layers

  • Anders Boström
  • Peter Bövik
  • Peter Olsson
Article

Abstract

In scattering problems for time-harmonic elastic waves, thin elastic layers are often of interest, e.g., in laminates. Various ways of substituting such layers by some effective boundary conditions have been proposed, and these are briefly reviewed. A rational way of obtaining boundary conditions that are exact to first order in the layer thickness is then described. For a thin spherical layer numerical comparisons are performed between these “exact” first order boundary conditions, the commonly used spring boundary conditions and the exact solution, and it is shown that the “exact” boundary conditions are far superior to the spring boundary conditions in most situations. A drawback with the “exact” boundary conditions is that they are quite complicated.

Key words

Elastic waves thin layers spring boundary conditions 

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Copyright information

© Plenum Publishing Corporation 1992

Authors and Affiliations

  • Anders Boström
    • 1
  • Peter Bövik
    • 1
  • Peter Olsson
    • 1
  1. 1.Division of MechanicsChalmers University of TechnologyGöteborgSweden

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