基于多层S型局域振子的声子晶体双层梁结构带隙特性研究

Band gap characteristics analysis of a phononic crystal double-layer beam structure based on multi-layer S-type local oscillator

针对工程中的振动噪声控制问题,提出了一种声子晶体梁结构,基于周期结构的Bloch定理,采用有限元法计算了该结构能带结构、特征模态所对应的位移场以及相应有限周期声子晶体梁结构的振动传输曲线,对其展现出的带隙特性进行了研究。由局域共振带隙形成主要机理,研究了低频段振动噪声控制的声子晶体梁结构,可应用于工程中特定频率的减振降噪问题。并对比分析了声子晶体单层梁结构和声子晶体双层梁结构的带隙特性,研究了单/双层梁结构振动的通性。研究了各参数对声子晶体梁结构带隙衰减频段的影响规律,通过合理设计参数,可以实现结构特定范围的低频隔振,在船舶、大型发电机组及其他工程的振动噪声领域中具有很好的应用前景。

To suppress the propagation of vibration and noise in practical engineering structures,a kind of phononic crystal beam structure was designed.Based on the Bloch theorem of periodic structures,the band structures,displacement fields of eigenmodes and transmission power spectrums of a finite periodic phononic crystal beam structure were calculated by finite element method.The exhibited band gap characteristics were studied.Based on the main mechanism of local resonant band gap formation,the phononic crystal beam structure used for the control of low frequency vibration and noise was studied.The structure could be applied to the vibration and noise reduction at specific frequency in engineering problems.The band gap characteristics of the phononic crystal veneer beam and phononic crystal double-layer beam were analyzed,and the general properties of the phononic crystal single/double layer beam were studied.The influences of various parameters on the attenuation band of the band gap of phononic crystal beam structures was studied,and the low frequency vibration isolation in a specific range can be realized through reasonable design of parameters.The structure proposed has a good application prospect in the field of vibration and noise reduction of ships and other engineering structures.