Sharma Gyani Shankar, Skvortsov Alex, MacGillivray Ian, Kessissoglou Nicole
School of Mechanical and Manufacturing Engineering, The University of New South Wales, Sydney, New South Wales, Australia.
Maritime Division, Defence Science and Technology Group, Melbourne, Victoria, Australia.
J Acoust Soc Am. 2017 Jun;141(6):4694. doi: 10.1121/1.4986941.
An approximate analytical model is presented to investigate sound transmission, reflection and absorption of a rubber-like medium comprising a single layer of periodic cylindrical voids attached to a steel backing. The layer of voids is modelled as a homogeneous medium with effective material and geometric properties. A numerical model based on the finite element method is developed to validate results from the homogenization model, as well as to show further insights into the physical mechanisms associated with the system acoustic performance. Monopole resonance of the voids is shown to reduce sound transmission through the voided medium due to increased reflection, resulting in poor sound absorption around this frequency. Peaks of high sound absorption are attributed to Fabry-Pérot resonance with the frequency of the first peak derivable by a lumped spring-mass analogy. Sound absorption for a single layer of voids in a soft elastic medium with a steel backing is shown to be similar to the sound absorption in the same elastic medium but without the steel backing, for a single layer of voids and its mirror image in the direction of sound propagation.
提出了一种近似解析模型，用于研究由附着在钢背衬上的单层周期性圆柱状空隙组成的类橡胶介质的声传播、反射和吸收。将空隙层建模为具有有效材料和几何特性的均匀介质。开发了基于有限元方法的数值模型，以验证均匀化模型的结果，并进一步深入了解与系统声学性能相关的物理机制。空隙的单极共振由于反射增加而减少了通过含空隙介质的声传播，导致在该频率附近吸声较差。高吸声峰值归因于法布里 - 珀罗共振，第一个峰值的频率可通过集总弹簧 - 质量类比推导得出。对于在软弹性介质中带有钢背衬的单层空隙，其吸声情况与在相同弹性介质中但没有钢背衬时、在声传播方向上单层空隙及其镜像的吸声情况相似。
