【摘要】 用平面波法研究了椭圆钢柱与环氧树脂组成的二维三角晶格声子晶体的带隙结构。结果表明,带隙的宽度和中心频率随填充率F或椭圆柱体横截面两半径之比T的变化表现出明显的变化规律;椭圆柱体横截面的对称性越高,带隙越宽;当F很小时,F对带隙中心频率的影响与T关系不大;椭圆柱体绕其中心轴旋转时,带隙的宽度呈现出与中心频率相反的变化规律,而且最小的带隙宽度及最高的中心频率均在柱体旋转60°左右出现。更多还原

【Abstract】 The plane wave expansion method was employed to calculate the band gap structures of 2D triangular lattice phononic crystal composed of elliptical steel cylinders embedded in epoxy matrix.Numerical results show that the width and mid-gap frequency of band gap reveal markedly change regulations when the filling fraction or the two radiuses’ ratio of elliptical cylinders’ cross section is altered;the higher the symmetry of elliptical cylinders’ cross section shape,the wider the band gap;the effect of on mid-gap frequency has less relation to at low filling fraction;band gap width reveals contrary change regulations to mid-gap frequency by rotating the elliptical cylinders around their central axes,the narrowest band gap and the highest mid-gap frequency appear at the cylinders are rotated about 60°.更多还原