压电复合材料结构的减振/致动性能优化

Optimization of vibration reduction/actuation performances of piezoelectric composite structures

压电复合材料由于其优越的机械能-电能转换能力,既可用于吸收结构振动能量进行减振,也可施加电压进行致动,但是针对减振与致动性能的设计异同点未被探讨与研究。针对碳纤维-玻璃纤维-压电纤维组成的多层压电复合材料结构的减振及致动性能进行设计与优化,给出了相应的结构铺层建议及优化结果。所设计的复合材料结构包括多层单向混合纤维复合基底和分布式压电片两个主要部分,基底中碳纤维、压电纤维和玻璃纤维对称铺设,压电片贴于基底最外层。基于Euler-Bernoulli梁理论及Hamilton原理推导了压电复合材料结构的机电耦合模型并分析其动力学特性。通过对比不同铺层顺序下结构的减振与致动性能,得到了混合控制结构的最佳铺层顺序。在此基础上,使用遗传算法对分布式压电片贴附位置和整体复合结构中的铺层角度进行优化,分别提升了结构的减振和致动性能。结果表明,分布式压电贴片在最外层时减振效果最好,压电层在内部时致动能力更优。压电贴片的贴附位置优化后,相比于在高应变区贴附的经验布置策略,前三阶模态减振性能分别提升了0.67 dB、0.77 dB及1.87 dB;碳纤维和玻璃纤维铺层角度分别为90.001 5°、53.065 2°时致动效果最佳。

Piezoelectric composite materials can be used to absorb structural vibration energy for vibration reduction or apply voltage on them for actuation due to their superior mechanical energy-electrical energy conversion capability. However, similarities and differences in design of their vibration reduction/actuation performances haven’t been discussed and studied. Here, vibration reduction/actuation performance of carbon fiber-glass fiber-piezoelectric fiber multilayer piezoelectric composite structure was designed and optimized, and the corresponding structural laying recommendations and optimization results were given. The composite structure designed included two main parts of multi-layer unidirectional hybrid fiber composite substrate and distributed piezoelectric sheets. Carbon fiber, piezoelectric fiber and glass fiber were symmetrically laid in substrate, and piezoelectric sheets were pasted on the outermost layer of substrate. Based on Euler-Bernoulli beam theory and Hamilton principle, the electromechanical coupling model of piezoelectric composite structure was derived and its dynamic characteristics were analyzed. By comparing vibration reduction/actuating performances of structures with different laying sequences, the optimal laying sequence of the hybrid control structure was obtained. Then, the genetic algorithm was used to optimize attachment positions of distributed piezoelectric patches and ply angle in overall composite structure, and improve vibration reduction and actuation performances of the structure, respectively. The results showed that distributed piezoelectric patches have the best vibration reduction effect when they are on the outermost layer, and inner piezoelectric layer has better actuating ability;after attachment positions of piezoelectric patches are optimized, vibration reduction performances for the structure’s first three modes are improved by 0.67 dB, 0.77 dB and 1.87 dB, respectively compared with the empirical placement strategy of attaching piezoelectric patches within high strain zone;when ply angles of carbon fiber and glass fiber are 90.001 5° and 53.065 2°, respectively, the actuating effect is the best.