摘要
在方柱简正方晶格每个原胞的中心插入另一个方柱形成复式结构固/气型声子晶体,采用平面波法计算了其弹性波带隙结构。结果表明,与简单晶格相比,复式结构能有效地降低晶格的对称性,使能带的简并态分离,有利于获得完全带隙,而且填充率越高,能带曲线的变化越平滑,带隙数目越多。此外,在相同的填充率下,最低带隙的宽度及中心频率都随着插入体尺寸的增大而增加,当插入体尺寸与原柱体相同时,可获得最宽的带隙。
The plane wave expansion method was employed to calculate the elastic wave band gaps of a phononic crystal with complex structure obtained by adding a smaller square rod at the center of each cell of simple square lattices.Numerical results showed that,the band gaps are easy to be opened and enlarged by reducing the symmetry of simple lattices to lift the degeneracy of bands;the larger the filling fractions,the smoother the bands,and the more the band gaps;with the same filling fraction,the widths and the mid-frequencies of the lowest band gaps increase by augmenting the cross section length ratio of inserters to the original rods,and the widest band gaps can be obtained when the ratio equals one.
出处
《振动与冲击》
EI
CSCD
北大核心
2010年第4期204-206,共3页
Journal of Vibration and Shock
基金
国家自然科学基金(10664006)
云南省基础研究计划(2007A0017Z)
文山学院校科研基金(08WSY06)资助项目
关键词
声子晶体
能带结构
弹性波带隙
平面波法
phononic crystal
band structure
elastic wave band gap
plane wave expansion method
