声学超材料型超轻多孔夹芯板的隔声机理与优化设计研究

Ultralightweight cellular sandwich structures are regarded as the most promising advanced lightweight, high-stiffness structures. Such structures possess high strength-to-weight ratio, leading to very bad sound insulation performance at low frequencies. It is of great interest to explore new method of sound insulation design for such structures. In this project, the concept of acoustic metamateirials are systematically introduced into the design of sandwich panels with ultralightweight cellular core. By attaching periodic arrays of artificial micro-structures (such as locally resonant units), a type of acoustic metamaterial sandwich panels with cellular core can be constructed. It is believed that such panels may exhibit similar unusual physical effects as acoustic metamaterials, so that the low-frequency sound insulation performance can be improved. In this project, we will first predict the sound insulation performance of acoustic metamaterial sandwich panels with cellular core. Then, we will explore the sound insulation mechanisms, and conduct optimal design to improve the sound insulation performance. Furthermore, experimental measurements will be conducted to confirm the theoretical results, as well as to evaluate the sound insulation performance of acoustic metamaterial sandwich panels with cellular core. Based on the studies, we will propose the method of sound insulation design for sandwich panels with ultralightweight cellular core based on the concept of acoustic metamaterials. The outcome of this project can promote the development of advanced lightweight structures with multi-functionalities.

超轻多孔夹芯结构被认为是最有前景的新一代先进轻质超强韧结构。这类结构具有质量轻、刚度大的特点，导致其低频隔声性能普遍较差，迫切需要研究其隔声设计的新方法。本项目拟将声学超材料原理系统引入到超轻多孔夹芯板结构的隔声设计，通过在超轻多孔夹芯板的表面或芯层内周期性地附加人工微结构单元（如局域共振单元），构建一类声学超材料型超轻多孔夹芯板结构，以期产生类似于声学超材料的超常物理效应，在轻质化条件下实现超常低频隔声性能。本项目将围绕声学超材料型超轻多孔夹芯板结构的隔声特性预报、隔声机理分析、隔声优化设计、隔声特性测试与评估等方面展开系统深入研究，由此提出基于声学超材料的超轻多孔夹芯板结构隔声设计新方法。研究成果有望推动承载、减重、隔声等多功能一体化先进轻质结构技术的发展。

隔声技术是实现飞机、火箭、高速列车等装备舱室噪声治理的一项主要技术，而实现隔声降噪的关键在于设计并采用具有高效隔声性能的隔声结构。然而，传统隔声结构受质量定律制约，在轻质薄层条件下无法高效地阻隔低频范围的噪声传播。.本项目将声学超材料原理系统引入到超轻多孔夹芯板结构的隔声设计，通过在超轻多孔夹芯板的表面或芯层内引入人工微结构单元，构建一类声学超材料型超轻多孔夹芯板结构，使其产生类似于声学超材料的超常物理效应，在轻质化条件下实现超常低频隔声性能。本项目围绕声学超材料型超轻多孔夹芯板结构的隔声特性预报、隔声机理分析、隔声优化设计、隔声特性测试与评估等方面展开系统深入研究。主要研究内容及结论包括：.(1) 提出了一种基于Bloch波分析的超轻多孔夹芯结构半解析动态等效方法，实现了多尺度超轻多孔夹芯结构的声振特性高效预报；.(2) 通过在点阵夹芯结构中引入机械共振式和声学共振式微结构单元，提出了基于点阵结构的两类声学超材料型超轻多孔夹芯板，系统分析了其隔声特性及隔声机理，研究表明，两类结构均可以在特定低频范围打破质量定律的限制，实现低频高效隔声。进一步采用差分进化算法，完成了隔声优化设计，实现了隔声性能的提升；.(3) 提出了一种基于多孔材料的声学超材料型超轻多孔夹芯板，并揭示了其低频隔声机理和参数调控规律，进而设计出了具有低频超宽带隔声性能的轻质薄层超材料型多孔夹芯板结构；.(4) 制备了典型的超材料型超轻多孔夹芯板样件，通过隔声测试验证了其低频宽带隔声性能。.总之，项目提出了基于声学超材料的超轻多孔夹芯板结构隔声设计新方法。研究成果有望推动承载、减重、隔声等多功能一体化轻质结构技术的发展，为解决新一代重大运载装备的舱室噪声治理问题提供前沿隔声结构技术支持。