基于“桥式”阻尼声学黑洞结构的振动抑制机理分析  

Vibration Suppression Analysis Based on“Bridge”Damping Acoustic Black Hole Structure

作　　者：汪恒 黄薇[2] 季宏丽[1] 裘进浩[1] WANG Heng;HUANG Wei;JI Hongli;QIU Jinhao(State Key Laboratory of Mechanics and Control of Aerospace Structures,Nanjing University of Aeronautics and Astronautics,Nanjing 210016;School of Mechanical Engineering,Nanjing University of Science and Technology,Nanjing 210094)

机构地区：[1]南京航空航天大学航空航天结构力学及控制国家重点实验室,南京210016 [2]南京理工大学机械工程学院,南京210094

出　　处：《机械工程学报》2024年第7期134-143,共10页Journal of Mechanical Engineering

基　　金：国家自然科学基金(52241103,U2241261,52105107);机械结构力学及控制国家重点实验室(南京航空航天大学)自主研究课题与开放课题(MCMS-I-0521G03,MCMS-E-0521Y01);机械系统与振动国家重点实验室(MSV202220)资助项目。

摘　　要：在工程中通常采用大面积敷设均匀阻尼材料的方式实现结构振动抑制,但是大量阻尼耗材的使用导致结构重量增加,而且振动抑制效率不高。声学黑洞(Acoustic black hole,ABH)作为一种新型轻质阻尼,通过结构厚度剪裁实现以高效波能量聚焦与耗散,近年来受到广泛关注。该研究提出“桥式”声学黑洞阻尼结构(Bridge-ABH,B-ABH)设计,将声学黑洞结构内嵌于阻尼层材料中,提升结构的振动能量耗散效率的同时减轻结构重量。通过有限元仿真建立B-ABH结构数值模型,研究了具有高损耗特征的B-ABH阻尼材料结构波能量传播特性。同时通过对B-ABH阻尼结构振动机械能流分析,探究了B-ABH结构特性对高阻尼材料中的能量耗散效率影响,揭示了B-ABH阻尼结构振动抑制机理。此外,采用附加质量进一步提升结构低频振动效果。研究结果表明,附加质量B-ABH阻尼结构相比较均匀阻尼层质量减少30%的同时,结构振动抑制在10~1 000 Hz频率范围内平均降低了4.6 dB。In the engineering,structural vibration suppression is usually achieved by pasting damping material over the host structure.However,the large usage of damping material leads to an increase of the structural weight.And the vibration suppression efficiency is not high.As a new type of lightweight damping,Acoustic black holes(ABHs)achieve high-efficiency wave energy focusing and dissipation through structural thickness tailoring.It has received widespread attention in recent years.A structural design of bridge-ABH(B-ABH)is proposed,which embeds the ABH feather in the damping material to improve the vibration energy dissipation efficiency of the structure with less amount of damping material.The numerical model of B-ABH structure is established by finite element method.The wave propagation characteristics in B-ABHs in damping materials with high loss characteristics are studied.And the mechanical energy flow analysis and damping characteristics of the B-ABH damping structures are analysed.The vibration suppression mechanism of B-ABH damping structure is revealed.In addition,the use of additional mass further improves the low-frequency vibration effect of the structure.The results show that compared with the uniform damping layer,the additional mass B-ABH damping structure is reduced by 30%.And the structural vibration suppression is reduced by an average of 4.6 dB in the frequency range of 10~1000 Hz.

关 键 词：声学黑洞 高阻尼 能量聚集 机械能流 

分 类 号：TH113[机械工程—机械设计及理论]