水下吸声机理与吸声材料

发布时间：2018-07-20 11:34

【摘要】：随着我国加速实施海洋强国战略,对先进水下吸声材料的需求日益迫切.与空气吸声不同,水下的高静水压力和复杂的海洋环境对水下吸声材料提出了更为苛刻的要求.吸声问题的本质是如何将弹性能高效地转化为热能或其他形式能量.本文综述了主要以聚合物分子内摩擦机制及界面耗能机制为基础的传统水下吸声材料.传统水下吸声材料面临的主要是其在低频及高静水压力下吸声性能差的问题.这是因为:一方面受质量密度定律的限制,有限厚度的水下吸声材料无法有效吸收水中传来的低频声波;另一方面,在高静水压力下,弹性材料如高分子聚合物会变"硬",从而大大降低了声波弹性能的转换效率.随着局域共振理论及超材料概念的提出,发展出了一系列新型水下吸声材料,为解决水下吸声材料遇到的难题提供了新思路.局域共振理论的特点是可以用小尺度结构控制长波声波的传播,从而可以解决低频吸声问题.本文重点综述了局域共振理论,以及由此发展出的声子木堆、声子玻璃等新型水下吸声材料.声子玻璃材料在局域共振理论基础上,通过引入多孔金属骨架结构提高了材料的抗压性能,从而解决了高静水压力下材料吸声性能变差的问题.本文最后对水下吸声材料未来发展方向进行了展望.
[Abstract]:With the rapid implementation of the strategy of ocean power in China, the demand for advanced underwater acoustical materials is becoming more and more urgent. Different from air sound absorption, high hydrostatic pressure and complex marine environment require more stringent underwater sound absorbing materials. The essence of the sound absorption problem is how to efficiently convert elastic energy into heat or other forms of energy. In this paper, traditional underwater acoustic absorbing materials based on internal friction mechanism and interfacial energy dissipation mechanism are reviewed. Traditional underwater acoustic absorbing materials are mainly faced with the problem of poor sound absorption under low frequency and high hydrostatic pressure. This is because on the one hand limited by the law of mass density, the limited thickness of underwater acoustic absorption materials can not effectively absorb the low-frequency sound waves from the water; on the other hand, under high hydrostatic pressure, Elastic materials, such as polymer polymers, become "hard", thus greatly reducing the conversion efficiency of acoustic elastic properties. With the development of the theory of local resonance and the concept of metamaterials, a series of new underwater acoustic absorbing materials have been developed, which provide a new idea for solving the problems encountered in underwater acoustic absorbing materials. The characteristic of local resonance theory is that the propagation of long wave acoustic wave can be controlled by small scale structure, thus the problem of low frequency sound absorption can be solved. In this paper, the theory of local resonance and the new underwater acoustic absorbing materials such as phonon pile and phonon glass are reviewed. Based on the theory of local resonance, the compressive performance of phonon glass material is improved by introducing porous metal skeleton structure, which solves the problem of poor sound absorption performance under high hydrostatic pressure. Finally, the future development of underwater acoustic absorption materials is prospected.
【作者单位】：中国科学院力学研究所中国科学院微重力重点实验室;海军装备研究院舰船所;
【基金】：国家自然科学基金项目(11202211,11602269) 中国科学院战略性先导科技专项(B类)(XDB22040301)资助
【分类号】：TB34

【相似文献】