经典模型在高度和的超声波传播中的分解
D Lafarge1, A Bouchendouka2, Z E A Fellah2
1Laboratoire d'Acoustique de l'Université du Mans (LAUM), (LAUM), UMR 6613, Institut d'Acoustique-Graduate School (IA-GS), CNRS, Le Mans Université, Le Mans, France.
The Journal of the Acoustical Society of America
|September 24, 2025
概括
标准的声学模型可能会因为具有强烈的吸声能力的工程孔隙泡而失败. 新的研究探讨了它们的局限性和改善吸音材料设计的潜力.
科学领域:
- 声学 声学 在声学方面
- 材料科学 材料科学 材料科学
- 物理 物理学 物理
背景情况:
- 孔隙泡的声学行为通常是使用约翰逊-阿拉德-香和相关理论来建模的.
- 这些模型对于具有中等流电阻的泡和用于噪声控制的简单微结构来说已经很成熟.
- 现有的模型可能需要对具有独特声学特性的先进材料进行改进.
研究的目的:
- 为了研究具有异常小的特征长度和强大的内在吸收能力的工程孔隙泡的声学性能.
- 识别当前声学模型 (例如,Johnson-Allard-Champoux) 在应用于这些先进材料时的潜在不足.
- 探索散射效应的出现及其对声音吸收的影响.
主要方法:
- 使用的自由场超声波 (约. 100 kHz) 和引导低频 (大约. 100 Hz) 的时间域测量.
- 实验探测了专门设计的多孔泡材料的声学行为.
- 分析了实验数据与已建立声学模型的预测之间的差异.
主要成果:
- 现有声学模型对于具有强烈内在吸收和小特征长度的工程泡显著不足.
- 观察到散射效应的潜在出现,这些效应并未完全被等效流体理论所捕获.
- 突出了现有模型在预测复杂毛孔几何形状的声音吸收方面的局限性.
结论:
- 当前的声学模型可能无法准确地描述具有独特微观结构和强吸收性的先进多孔材料的行为.
- 研究结果表明,需要扩展现有模型,以纳入散射效应,以获得更全面的理解.
- 开辟了设计新型宽带吸声结构的途径,通过受控反射提高了性能,特别是在低频率下.
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