双层超材料板的带隙特征与隔声性能研究

Study on Bandgaps and Sound Insulation Properties of Metamaterial Bipanel

通过设计槽形双环共振单元,构造正方点阵、三角点阵双层超材料板,采用有限元法计算他们的弯曲波低频带隙,而局域共振产生负的动态质量密度的频率段与带隙很好地吻合。对于相同晶格常数和材料组分条件下,在弯曲波带隙频率范围分析正方点阵、三角点阵双层超材料板的双环旋转角β、声波入射角θ对隔声量STL的影响。与常见同质量均质双层板比较,这种新型双层超材料板具有频率低、结构简单、体积小等优点,在减振降噪工程领域有着广阔应用前景。

By designing dual-ring resonance units,the metamaterial bipanels with square and triangular lattices are constructed.Their low-frequency bandgaps of flexural waves are calculated by using the finite element method.The results show that the frequency range of negative dynamic mass density caused from the local resonance is in a good agreement with that of the bandgap.Under the same lattice constant and material component conditions,the effects of rotation angleβof dual-ring and the acoustic wave incidence angleθon the sound transmission loss are analyzed in the bandgap range of flexural wave for the metamaterial bipanels with the square and triangular lattices.Compared with the traditional homogeneous bipanels with the same mass,these new metamaterial bipanels have the advantages of low frequency,simple structure and small size,which have a wide application prospect in vibration and noise control.