Wavevector resonance in a nonlinear multi-wavespeed chaotic billiard

Alexei Akolzin; Richard L. Weaver

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arXiv · nlin/0601018

Wavevector resonance in a nonlinear multi-wavespeed chaotic billiard

Alexei Akolzin·Richard L. Weaver

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Abstract

Nonlinear coupling between eigenmodes of a system leads to spectral energy redistribution. For multi-wavespeed chaotic billiards the average coupling strength can exhibit sharp discontinuities as a function of frequency related to wavevector coincidences between constituent waves of different wavespeeds. The phenomenon is investigated numerically for an ensemble of 2D square two-wavespeed billiards with rough boundaries and quadratic nonlinearity representative of elastodynamic waves. Results of direct numerical simulations are compared with theoretical predictions.

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Alexei Akolzin, Richard L. Weaver. 2006-01-06. Wavevector resonance in a nonlinear multi-wavespeed chaotic billiard. https://arxiv.org/abs/nlin/0601018

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