包含共振机理的声子晶体声屏障设计与降噪性能测试

针对轮胎-路面噪声,基于U型理论模型探究并优化了3种腔体形式声子晶体的能带结构,最终设计出一种"宽频多带"的沙漏型声子晶体,并以此为基础建立了新型交通声屏障,且进行了降噪性能测试.结果表明:对于噪声特征频段覆盖率,沙漏型＞锥型＞直线型,且禁带范围可通过腔体尺寸进行有效调整;对于声子晶体声屏障降噪效果,将Bragg散射与...

Design and experimental research of sonic crystal noise barrier with resonance mechanism

In order to reduce the tire-road noise, this study optimized the band structure of the three cavity forms based on the U-shaped model. A "broadband and multi-band" hourglass sonic crystal was designed, then a new type of noise barrier was established and tested for noise reduction performance. The results showed that for the noise characteristic frequency band coverage, hourglass>taper in>straight, and the band gap range can be effectively adjusted by changing the cavity size. For the noise reduction performance of sonic crystal noise barrier, Bragg scattering and cavity resonance effect were coupled and the number of rows can be increased to improve the noise reduction effect in the band gap by 0.9~3.5dB(A). As a discontinuous periodic structure, the noise reduction effect after the barrier was unevenly distributed, especially between the scatters, therefore, when measuring, the number of measuring points should be increased and the influence of the interval should be considered. Compared with the traditional noise barrier and the Bragg-type sonic crystal noise barrier, the noise reduction effect of hourglass type was improved by 0.9~14dB(A) in the 500~1000Hz target frequency band gap.