基于二维声学黑洞结构的面板振动噪声控制理论

Theory of vibration and noise control of panel based on two-dimensional acoustic black hole structure

研究了非理想二维声学黑洞结构对振动噪声控制的影响。建立了一种嵌入非理想二维声学黑洞结构平板的有限元和边界元仿真分析模型,从模态、频率响应、振动功率流和辐射噪声4个方面对比了这种非理想二维声学黑洞结构和理想声学黑洞结构、普通平板的动力学及声学特性,分析了非理想二维声学黑洞对结构减振降噪的影响。结果表明,非理想二维声学黑洞结构的工作频段主要集中在中高频,低频作用不明显。所设计的非理想二维声学黑洞结构具有能量聚集效应,同时改变了结构的固有频率,可避免与激励源振动频率相同而产生共振,达到减振的作用。通过粘贴阻尼片进行能量耗散,保证在结构整体质量无增加的前提下,可以达到减小结构振动、降低辐射噪声的效果。

The effect of non-ideal two-dimensional acoustic black hole(NTDABH) structure on vibration and noise control was studied.A finite element and boundary element simulation analysis model of panel embedded noni-deal two-dimensional acoustic black hole was established,the dynamic and acoustic characteristics of this NTDABH structure,ideal acoustic black hole structure and ordinary flat panel were compared from four aspects of mode,frequency response,vibration power flow and radiation noise,and the influence of NTDABH on vibration and noise reduction of structures was analyzed.The results show that the working frequency band of the NTDABH structure is mainly concentrated in the middle and high frequency,and the low frequency effect is not obvious.This designed NTDABH structures have the energy accumulation effect,and the natural frequency of the structure is changed,which can avoid resonance caused by the same vibration frequency as the excitation source,so as to achieve the vibration reduction effect.The energy is dissipated by sticking damping plate to guarantee that the structure vibration and radiation noise can be reduced without increasing the overall mass of the structure.