基于磁流变弹性体的声子晶体带隙隔振研究

Band Gap Vibration Isolation of Phononic Crystals Based on Magnetorheological Elastomers

设计了一种基于磁流变弹性体的二维声子晶体隔振器,可用于中高频的机械设备隔振,并对其带隙特性进行分析。以圆柱形铅散射体按正方晶格排列在基体磁流变弹性体当中的二维声子晶体为模型,采用典型的平面波展开法和有限元法研究其能带结构和透射特性,分别计算了不同磁场和不同铁颗粒体积分数情况下声子晶体的带隙,并对禁带范围内的某一频率的位移场进行分析。结果表明:两种方法所计算的带隙结果吻合较好,最大误差为4.9%;铁颗粒体积分数保持不变,增大磁感应强度可以同时增加带隙的位置和宽度;一定的磁场环境下,增加铁颗粒体积分数,带隙位置上移,宽度基本不变;某一频率处,声子晶体的内部波场存在着共振现象。

A two dimensional phononic crystal isolator based on magnetorheological elastomers is designed,which can be used for vibration isolation of mechanical devices at medium and high frequencies,and the characteristics of band gap are analyzed.For 2-D phononic crystals with cylindrical lead embedded in the matrix MRE in form of square lattice,the band structure and transmission characteristics are studied by the typical plane wave expansion and finite element method.The band gap of the phononic crystals in different magnetic fields as well as in different volume fraction of iron particles of matrix MRE is calculated.The displacement field of a certain frequency within bandgap is also analyzed with finite element method.The result of bandgap calculated with plane wave expansion agrees well with that with finite element method,and the maximum error is 4.9%.With volume fraction of iron particles unchanged,the location and width of the band gap can be regulated simultaneously by an increasing magnetic induction intensity.In a definite magnetic field,the position of the band gap moves up while the width is basically unchanged by an increasing volume fraction of iron particles.At some frequencies,there is resonance phenomenon in the wave field of two-dimensional lead/MRE phononic crystal.