全向入射条件下一维固流周期结构中低频声裂隙变化特性研究

摘要

In order to study the characteristics of acoustic/elastic wave propagation in one-dimensional (1D) solid-fluid periodic structure incited by omnidirectional incidence, a theoretical model of wave propagation in 1D solid-fluid periodic structure is established using a transfer matrix method. Based on this model, the band structures of the infinite case and the transmission properties of the finite one are further calculated and analyzed. The results show that an acoustic band fracture appears in the low frequency transmission zone for a certain incident angle. The corresponding incident angle of the fracture is non-relevant to the mass densities or the thicknesses of the solid and fluid layers constituting the periodic structure, and determined only by the wave velocity of the constituent material.%利用传递矩阵法，从理论上建立了全向入射条件下一维固-流周期结构中的声传播模型，在此基础上计算、分析并比较了无限周期结构的声能带结构和有限周期结构中的声传输特性。研究结果表明，当声波以一定的入射角入射时，固-流周期结构的低频通带区域存在一个声裂隙，该声裂隙所对应的入射角大小与构成周期结构的固体层和流体层的密度或结构尺寸无关，而仅取决于构成该周期性结构材料的波速。