在双孔气的随机分布中的声波波
1Laboratoire Ondes et Milieux Complexes (LOMC) UMR CNRS 6294, 75 rue Bellot, Université Le Havre Normandie, Le Havre, France.
Ultrasonics
|November 18, 2023
概括
这项研究使用通用自相一致的方法调查随机分布的双孔气的有效性. 结果揭示了对波浪传播和孔隙性的依赖,以提高材料特性.
科学领域:
- 声学超材料是一种声学超材料.
- 在异质介质中的波传播.
- 有效媒介理论 有效媒介理论
背景情况:
- 了解复杂介质的有效性质对于材料设计至关重要.
- 以前的模型往往简化了散射相互作用或多孔性结构.
- 由于相互连接的毛孔网络,双孔系统存在独特的挑战.
研究的目的:
- 为了确定随机分布的双孔气的有效波数,散装模量和质量密度.
- 应用和检查通用自相一致方法 (GSCM) 与林顿和马丁的公式结合.
- 分析这些异质结构中的低频行为和波浪依赖性.
主要方法:
- 将通用自相一致方法 (GSCM) 应用于林顿和马丁的公式.
- 对平行圆圆圆筒之间多重散射效应的分析.
- 在GSCM框架内检查独立散射近似法 (ISA).
- 低频率隐式方程的分析解决方案.
主要成果:
- 实际属性 (波数,散体模量,质量密度) 为指定的几何形状推导.
- 证明GSCM对多个散射场景的适用性.
- 对双孔性材料的低频声响应的洞察.
- 散射器体积分数和多孔度对有效性质的影响的说明.
结论:
- GSCM提供了一个强大的框架,用于描述复杂的异质介质的有效性质.
- 波传播特征 (P1,P2,P3,S波) 显著影响宏观行为.
- 孔径和散射器分布是控制有效声响应的关键参数.
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