Rohlfing J, Gardonio P
Institute of Sound and Vibration Research, University of Southampton, Southampton, United Kingdom.
J Acoust Soc Am. 2009 Jun;125(6):3696-706. doi: 10.1121/1.3123405.
In this paper an element-based model is used to predict the structural response and sound radiation of two smart panels excited by (a) an acoustic plane wave, (b) a stochastic acoustic diffuse field, and (c) a turbulent boundary layer. The first panel is made of aluminum, while the second is a composite sandwich panel with equivalent static stiffness but four times lower mass per unit area. The panels are equipped with 16 decentralized velocity feedback control loops using idealized point force actuators. In contrast to previous studies on smart panels, the analysis is extended to the upper end of the audio frequency range. In this frequency region the response and sound radiation of the panels strongly depend on the spatial characteristics of the excitation field and the sound radiation properties with respect to the bending wavelength on the panels. Considerable reduction in structural response and sound radiation is predicted for the low audio frequency range where the panel response is dominated by well separated resonances of low order structural modes. It is also found that some reduction can be achieved around acoustic and convective coincidence regions.
在本文中，基于单元的模型用于预测两块智能面板在以下激励下的结构响应和声辐射：(a) 平面声波，(b) 随机声学扩散场，以及 (c) 湍流边界层。第一块面板由铝制成，而第二块是具有等效静态刚度但单位面积质量低四倍的复合夹芯板。面板配备了16个使用理想化点力致动器的分散式速度反馈控制回路。与先前关于智能面板的研究不同，分析扩展到了音频频率范围的高端。在该频率区域，面板的响应和声辐射强烈依赖于激励场的空间特性以及与面板上弯曲波长相关的声辐射特性。对于低频音频范围，预计结构响应和声辐射会有显著降低，在该范围内面板响应由低阶结构模态的良好分离的共振主导。还发现，在声学和对流重合区域周围可以实现一定程度的降低。
