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arXiv · 1608.04623

Ray and wave scattering in smoothly curved thin shell cylindrical ridges

Abstract

We propose wave and ray approaches for modelling mid- and high- frequency structural vibrations through smoothed joints on thin shell cylindrical ridges. The models both emerge from a simplified classical shell theory setting. The ray model is analysed via an appropriate phase-plane analysis, from which the fixed points can be interpreted in terms of the reflection and transmission properties. The corresponding full wave scattering model is studied using the finite difference method to investigate the scattering properties of an incident plane wave. Through both models we uncover the scattering properties of smoothed joints in the interesting mid-frequency region close to the ring frequency, where there is a qualitative change in the dynamics from anisotropic to simple geodesic propagation.

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Niels Sondergaard, David Chappell. 2016-08-16. Ray and wave scattering in smoothly curved thin shell cylindrical ridges. https://doi.org/10.1016/j.jsv.2016.05.019

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