Turbulence in cavity acoustic black hole. (15th February 2022)

• Record Type: Journal Article
• Authors: Liang, Xiao; Chu, Jiaming; Zhou, Zhuo; Hu, Congfang; Peng, Jinfeng; Liu, Baixi; Mo, Lin; Wu, Jiu Hui; Lin, Mei
• Is Part Of: Mechanical systems and signal processing. Volume 165(2022)
• Publication Date: 2022-02-15
• Subjects: Cavity acoustic black hole -- Turbulence -- Sound energy dissipation characteristics -- Nonlinear thermoviscous acoustic model; Structural dynamics -- Periodicals; Vibration -- Periodicals; Constructions -- Dynamique -- Périodiques; Vibration -- Périodiques; Structural dynamics; Vibration; Periodicals; 621
• DOI: 10.1016/j.ymssp.2021.108303
• Languages: English
• ISSNs: 0888-3270

Abstract

Abstract: In this paper, we adopt both numerical and experimental approaches to investigate the turbulent flow in a cavity Acoustic Black Hole (ABH), and the low frequency sound energy dissipation mechanism under turbulence. Through the simulation by thermoviscous acoustic module, we deeply study the turbulent development process of the fluid acoustic medium in the cavity ABH, and how the turbulent evolution determines the acoustic performance of the ABH. This dissipation mechanism caused by turbulence in ABH enables cavity acoustic black hole to isolate more than 90% low frequency sound waves in an ultra-low and ultra-broad band, which can provide a good technical solution for the isolation of low frequency sound waves. Our experimental results not only prove our simulation and numerical results, but also prove an important theoretical result of turbulence theory, that is, in fully turbulence state, the relationship between turbulence energy spectral density E and wave number k ( k = 1/ L, L is the characteristic size L ) is E ~ k −3 .