摘要：Design and application of tunable phononic crystals(PnCs)are attracting increasing interest due to their promising capabilities to manipulate acoustic and elastic waves *** paper investigates topology optimization of the magnetorheological(MR)materials including PnCs for opening the tunable and wide ***,the bandgap tunability of the PnCs is achieved by shear modulus variation of MR materials under a continuously changing applied magnetic *** pseudo elemental densities representing the bi-material distribution inside the PnC unit cell are taken as design variables and interpolated with an artificial MR penalization *** aggregated bandgap index for enveloping the extreme values ofbandgap width and tunable range of the MR included smart PnCs is proposed as the objective *** this context,the sensitivity analysis scheme is derived,and the optimization problem is solved with the gradient-based mathematical programming *** effectiveness of the proposed optimization method is demonstrated by numerical examples,where the optimized solutions present tunable and stably wide bandgap characteristics under different magnetic *** tunable optimized PnCs based device that can provide a wider tunable bandgap range is also explored.

摘要：压电超材料在带隙调控方面已经得到了广泛的应用,然而,在工程应用中,宽带振动抑制是仍存在着挑战.在本文中,设计了一中包含多个压电单元的压电超胞结构,并提出一种压电超材料梁的优化方法用于拓宽超材料振动抑制的频率范围.采用遗传算法对压电单元中的LR分流电路进行优化.通过优化将多个局部共振带隙耦合到布拉格带隙中.同时可定制超材料的衰减常数,并优化得到最大带宽.为验证优化方法的正确性以及宽频振动抑制能力,利用合成电路模拟LR电路中的可调电感,通过调节电感,实验实现了可调节的振动抑振能力.实验结果还表明,优化后的超材料可拓宽振动抑制频率范围.实验验证了超材料宽频可调节的振动抑振能力.本文为宽带振动抑制提供了一种新的方法和途径.