Analysis of Sound Absorption Characteristics of Acoustic Ducts with Periodic Additional Multi-Local Resonant Cavities

Junyi Liu,Ting Wang,Meixia Chen

doi:10.3390/sym13122233

Abstract

With the aim of applying various Helmholtz resonant cavities to achieve low-frequency sound absorption structures, a pipe structure with periodic, additional, symmetrical, multi-local resonant cavities is proposed. A thin plate with additional mass is placed in the cylindrical Helmholtz resonant cavity structure to form a symmetric resonant cavity structure and achieve multi-local resonance. The simulation results show that the periodic structure proposed in this paper can produce multiple, high acoustic transmission loss peaks and multiple lower broadband sound absorption frequency bands in the low-frequency range. In this paper, this idea is also extended to the Helmholtz resonant cavity embedded with multiple additional mass plates. The results show that the periodic arrangement of the multi-local resonant symmetric cavity inserted into multiple plates with mass can significantly increase its transmission loss and show a better performance on low-frequency sound absorption characteristics.

Highlights

Can noise affect the use and performance of the apparatus, but noise pollution can negatively affect human health
This affects the sound radiation performance of ships and submarines, reduces their stealth performance, and seriously affects their survivability and combat effectiveness; the design of a pipeline system with effective sound absorption characteristics is vital for noise control
This paper focuses on the design of a periodic, multi-local, resonant, local-resonance acoustic pipe structure that can be applied to underwater ships and sea-to-sea pipelines

Summary

Introduction

Can noise affect the use and performance of the apparatus, but noise pollution can negatively affect human health. The Helmholtz resonator is employed widely in the field of noise control due to its simple structure and excellent acoustic properties [3], such as its application in ducts for its effective sound absorption characteristics [4]. Langfeldt et al [7] designed Helmholtz resonators with multiple necks and obtained the explicit equations to explain the acoustic performances of their structure. Shen et al [18] devised a fluid-filled pipe of dark acoustic metamaterial type and proved its ability to produce extra-wide bandgaps in the low-frequency range to achieve noise reduction It can be concluded through many studies that considering the elasticity of the wall and inserting the elastic structures into a Helmholtz cavity can develop effective sound absorption characteristics. To the study, and the wave vector is used to to obtain the energy band structure diagram

Acoustic Pipe with Periodic Multiple Local Resonant Cavities

Conclusions