谐振放大压电声学超材料梁带隙特性研究  

Band-gap properties of piezoelectric acoustic metamaterial beams with amplified resonant shunts

作　　者：陈圣兵[1] 张浩 宋玉宝[1] 贺旭照[1] CHEN Sheng-bing;ZHANG Hao;SONG Yu-bao;HE Xu-zhao(China Aerodynamics Research and Development Center,Mianyang 621000,China)

机构地区：[1]中国空气动力研究与发展中心,四川绵阳621000

出　　处：《振动工程学报》2022年第3期550-556,共7页Journal of Vibration Engineering

基　　金：国家自然科学基金资助项目(11702306,51805530)。

摘　　要：声学超材料具有亚波长带隙,可应用于结构振动与噪声控制。引入压电材料和谐振分流电路,可以利用电磁振荡和压电材料机电耦合特性在超材料内部形成可调谐局域共振带隙。传统压电声学超材料受到已有压电材料机电耦合系数的限制,带隙一般较窄,无法满足大柔性结构振动与噪声控制中低频宽带需求。因而,该文提出一种谐振放大压电声学超材料梁结构。将压电片划分为传感极和驱动极,传感极输出电压经过运算放大电路放大,然后与谐振电路相连,实现局域共振效果的增强,从而增大带隙宽度。采用有限元方法建立压电声学超材料梁带隙计算模型,分析了带隙位置和宽度随电路放大倍数的变化,研究了等效弹性模量与带隙的关系;利用商用有限元软件仿真分析了有限周期梁的振动传递特性,验证了带隙计算方法的正确性。研究结果表明,放大电路有效增强了电路的局域共振效果,随着放大倍数的增大,带隙频率降低,带隙宽度增大。Acoustic metamaterials have sub-wavelength band gaps,which can be applied to noise and vibration control.With the introduction of piezoelectric materials and resonant shunts,tunable locally resonant band gaps can be achieved by utilizing their electromechanical coupling and electromagnetic oscillation.However,restricted by the limited electromechanical coupling coefficients of available piezoelectric materials,the band width of traditional piezoelectric acoustic metamaterials is generally narrow,which is barely to satisfy the requirement of low-frequency and broad band gaps in noise and vibration of flexible structures.Consequently,this paper proposes a type of piezoelectric acoustic metamaterials with amplified resonant shunts.Piezoelectric patches are partitioned into sensing poles and driving poles.The output voltage of the sensing pole is amplified by an operational amplifier circuit.The amplified voltage is applied on a resonant shunt to enhance the local resonance and broaden the band width.Finite element method is adopted to build the mathematical model and evaluate the band gaps.Also,the variations of band location and width with amplification coefficient are analyzed,including the relation between equivalent modulus and band gaps.The commercial finite element software is employed to analyze the vibrational transmission of the finite periods beam and validate the calculation method of band gaps.The investigation results demonstrate that the locally resonant effect can be effectively enhanced by amplification circuits.The band frequency decreases with the increasing of amplification coefficient,whereas the band width increases accordingly.Hence,this work is of great importance in design of low frequency and broad band piezoelectric acoustic metamaterials.

关 键 词：声学超材料 振动控制 带隙 压电分流 

分 类 号：O735[理学—晶体学] TB535[理学—物理]