Lee Joong Seok, Yoo Sungmin, Ahn Young Kwan, Kim Yoon Young
Institute of Advanced Machines and Design, Seoul National University, 1 Gwanak-ro, Gwanak-gu, 151-744 Seoul, Republic of Korea
Department of Mechanical and Aerospace Engineering, Institute of Advanced Machines and Design, Seoul National University, 1 Gwanak-ro, Gwanak-gu, 151-744 Seoul, Republic of Korea
J Acoust Soc Am. 2015 Sep;138(3):EL217-22. doi: 10.1121/1.4929625.
This paper investigates the feasibility of broadband sound blocking with rotationally symmetric extensible inclusions introduced in phononic crystals. By varying the size of four equally shaped inclusions gradually, the phononic crystal experiences remarkable changes in its band-stop properties, such as shifting/widening of multiple Bragg bandgaps and evolution to resonance gaps. Necessary extensions of the inclusions to block sound effectively can be determined for given incident frequencies by evaluating power transmission characteristics. By arraying finite dissimilar unit cells, the resulting phononic crystal exhibits broadband sound blocking from combinational effects of multiple Bragg scattering and local resonances even with small-numbered cells.
本文研究了在声子晶体中引入旋转对称可扩展内含物实现宽带隔音的可行性。通过逐渐改变四个形状相同的内含物的尺寸，声子晶体的带阻特性发生了显著变化，如多个布拉格带隙的移动/拓宽以及向共振隙的演变。通过评估功率传输特性，可以确定给定入射频率下有效隔音所需的内含物扩展量。通过排列有限个不同的单位晶胞，即使晶胞数量较少，所得声子晶体也能通过多种布拉格散射和局部共振的组合效应实现宽带隔音。
