考虑挠曲电效应的薄板声学超材料隔声特性研究

Study on Sound Insulation Characteristics of Thin Plate Acoustic Metamaterials With Flexoelectric Effects

区别于传统的压电效应,当结构尺寸减小到微纳米尺度时,一种新的力电耦合效应——挠曲电效应将无法被忽略.该文利用变分原理推导了考虑挠曲电效应的薄板声学超材料结构隔声问题的控制方程和边界条件,基于Kirchhoff薄板理论预测了薄板质量块结构的隔声曲线,系统讨论了挠曲电效应、几何尺寸、质量密度等参数对结构隔声性能的影响.结果表明,当结构尺寸减小到微纳米尺度时,挠曲电效应显著增加了隔声曲线的隔声谷值和峰值频率,因此考虑挠曲电效应是十分有必要的.该文的工作有望为微机电系统的噪声控制研究提供理论基础.

When the structure size is reduced to the micro-and nano-scale,a new mechanoelectric coupling effect,the flexoelectric effect,cannot be ignored.The governing equations and boundary conditions for the sound insulation problem of thin plate acoustic metamaterial structure with the flexoelectric effects were derived by means of the variational principle.The sound insulation curves of thin plate mass blocks were predicted based on the Kirchhoff theory.The effects of flexural effects,geometric sizes and mass densities on the sound insulation performances of the structure were systematically discussed.The results show that,for the micro-and nano-scale structure sizes,the flexoelectric effect significantly increases the sound insulation valley values and peak frequencies of the sound insulation curves,so it is necessary to consider the flexoelectric effects.This work provides a theoretical basis for the research of noise control in MEMS.