This article considers the computational (acoustic) wave propagation in strongly heterogeneous structures beyond the assumption of periodicity. A high contrast between the constituents of microstructured multiphase materials can lead to unusual wave scattering and absorption, which are interesting and relevant from a physical viewpoint, for instance, in the case of crystals with defects. We present a computational multiscale method in the spirit of the Localized Orthogonal Decomposition and provide its rigorous a priori error analysis for two-phase diffusion coefficients that vary between $1$ and very small values. Special attention is paid to the extreme regimes of high frequency, high contrast, and their previously unexplored coexistence. A series of numerical experiments confirms the theoretical results and demonstrates the ability of the multiscale approach to efficiently capture relevant physical phenomena.

中文翻译：

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来自高对比度异质介质的计算高频散射

本文考虑了超出周期性假设的强异质结构中的计算（声）波传播。微结构多相材料成分之间的高对比度会导致不寻常的波散射和吸收，从物理角度来看，这很有趣且相关，例如，在晶体有缺陷的情况下。我们本着局部正交分解的精神提出了一种计算多尺度方法，并为在 $1$ 和非常小的值之间变化的两相扩散系数提供其严格的先验误差分析。特别注意高频、高对比度的极端情况，以及它们以前未探索过的共存。