由于三维表面粗而导致雷利波的减弱:一个全面的数值评估
Georgios Sarris1, Stewart G Haslinger2, Peter Huthwaite1
1Department of Mechanical Engineering, Imperial College London, London SW7 1AY, United Kingdom.
The Journal of the Acoustical Society of America
|August 11, 2023
概括
这项研究使用有限元素 (FE) 建模来分析由表面粗引起的雷利波衰减. 结果证实了所有散射模式的理论预测,并将其扩展到新的场景.
科学领域:
- 固体机械学 固体机械学
- 声学 声学 在声学方面
- 波浪的传播方式
背景情况:
- 由于表面粗而导致的雷利波衰减是一个已知的现象.
- 三种散射模式 (雷利,随机,几何) 不同地描述了这种衰减.
- 现有的理论在范围和适用性方面有局限性.
研究的目的:
- 通过有限元 (FE) 建模在三维中研究雷利波衰减.
- 在所有散射模式中对现有的理论预测进行FE建模验证.
- 将减弱的理解扩展到超出当前理论限制的情况.
主要方法:
- 使用了三维有限元素 (FE) 建模.
- 采用统一的FE方法,适用于所有分散模式.
- 将FE模拟结果与已建立的理论模型进行比较.
主要成果:
- FE建模与雷利波衰减的理论预测有很好的一致性.
- 这项研究成功地验证了FE在雷利,随机和几何散射模式中的方法.
- 对现有理论范围之外的条件产生了新的结果.
结论:
- 有限元建模为研究雷利波衰减提供了一个强大的和统一的方法.
- FE方法验证和扩展现有的表面粗效应理论.
- 这项工作为更广泛的应用提供了对波衰减现象的新见解.
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