Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Sound energy control in a wide frequency domain by a hybrid acoustic material
Submission Author:
Gildean Almeida , SC , Brazil
Co-Authors:
Gildean Almeida, Erasmo Felipe Vergara, Leandro Barbosa, Lucas Roussenq Zanatta, Kleyton Zimmermann, Robson Zdebski Mikulksi, Victor Bahú
Presenter: Victor Bahú
doi://10.26678/ABCM.COBEM2023.COB2023-0163
Abstract
The evolution of acoustic materials allowed the development of structures for the control of sound energy. However, consolidating this control over a wide spectrum of frequencies is a challenging task, especially when designing structures and devices with small dimensions. In this work, a hybrid acoustic material is proposed to control sound energy in a wide range of frequencies based on the combination of a porous material layer and a modified Helmholtz resonator. Theoretical equivalent fluid models and numerical simulations using the finite element method (FEM) are used to describe the behavior of the hybrid absorber. In addition, experimental tests are conducted on an impedance tube apparatus using the standard two-microphone method. The results obtained showed good agreement. Furthermore, the bandwidth factor (Q_α) made it possible to evaluate the expanded sound energy control range. In this sense, a Q_α = 90% in the frequency range between 100 Hz and 3000 Hz was achieved experimentally. It was observed that the type and thickness of the porous material layer produce a strong influence on the energy control. Finally, this work contributes to the understanding the propagation of sound waves in a hybrid acoustic material, as well as to evolution of sound energy control through these materials.
Keywords
sound absorption, Helmholtz resonator, Hybrid acoustic material, Equivalent fluid
