吸声特性可调的IPMC周期性低频吸声结构换能机理及其优化设计与调控

构建可调控的亚波长厚度低频吸声体不仅是声学领域亟需解决的难题，也是国防和民用工业共同关注的热点方向。针对低频吸声对于非线性、高耗能、易调控材料和结构的研究需求，申请人提出基于IPMC材料的低频响应和振动特性以及力电双向转换功能机制，构筑吸声性能可调的周期性低频吸声结构。项目拟结合MPP结构共振单元设计，探索单元结构及材料内部微/纳米孔隙、颗粒和固液界面特征对吸声性能的影响规律；通过分析弹性波和电压作用下质量（离子/溶剂）动态传递过程，建立吸声体多场耦合模型，揭示弹性波能量转换机制；通过研究单元组装的电化学场耦合作用，揭示IPMC周期性结构的协同吸声机制及阻抗匹配原则；在此基础上，研究IPMC曲面驱动器的多自由度大变形控制，及其对吸声体局域力电参数、固有频率乃至吸声性能的影响规律和机理。研究成果有望为可调控低频吸声体提供理论和实验解决方案，也为柔性智能材料的致动传感一体化应用开辟新的思路。

The construction of low frequency sound absorption structure with subwavelength thickness and adjustable absorption characteristics is not only an urgent problem in the field of acoustics, but also a hot topic in the field of both national defense and civil industry. In view of the research demand of non-linear, high-energy-consumption and easy-to-control materials and structures for low-frequency sound absorption, the applicant proposes to build a periodic low-frequency sound absorption structure with adjustable sound absorption performance based on the low-frequency response and vibration characteristics of IPMC materials and the bidirectional mechanical and electric conversion mechanism. The project plans to explore the influence of the unit structure and the micro / nano pore, particle and solid-liquid interface characteristics of the material on the sound absorption performance, in combination with the design of the MPP structure resonance unit; establish the multi-field coupling model of the absorber and reveal the energy conversion mechanism of the elastic wave by analyzing the dynamic transfer process of the mass (ion/solvent) under the action of the elastic wave and voltage; reveal the mechanism of synergistic sound absorption and the principle of impedance matching of periodic structure by investigating the coupling effect of the electrochemical field in cell assembly study; and on the basis, study the M-DOF and large deformation control of the IPMC surface actuator and its influence on the local electromechanical parameters, natural frequency and sound absorption performance. The research results are expected to provide theoretical and experimental solutions for the adjustable low-frequency absorbers, and also open up new ideas for the integrated application of flexible intelligent materials in actuation sensing.