Effects of the Top Edge Impedance on Sound Barrier Diffraction

Applied Sciences

Xiaojun Qiu¹  Xiaofan Huang²  Haishan Zou² 

[1] Centre for Audio, Acoustics and Vibration, Faculty of Engineering and IT, University of Technology Sydney, Ultimo 2007, Australia;Key Laboratory of Modern Acoustics (MOE), Institute of Acoustics, Nanjing University, Nanjing 210093, China;

关键词: noise barrier;    top edge impedance;    integral equation method;   

DOI  :  10.3390/app10176042

来源: DOAJ

【 摘 要 】

Sound barriers can be configured with different top edge impedance to improve their noise control performance. In this paper, the integral equation method was used to calculate the sound field of a barrier with various top edge impedance, and the effects of the barrier top edge impedance on sound barrier diffraction were investigated. The simulation results showed that the noise reduction performance of a sound barrier with a soft boundary on its top edge was larger than that with a hard boundary, but there were some impedance values which, if assigned to the top edge boundary, would give the sound barrier even better noise reduction performance. It was found that the sound barrier with a good top edge impedance formed a dipole-like radiation pattern above the barrier to expand the effective range of the shadow zone. The research discoveries reported in this paper point out the potentials of using acoustics metamaterials or active control methods to implement the desired good impedance on the top edge of a sound barrier for better noise reduction.

【 授权许可】

Unknown