为了抑制车内中低频噪声,运用板件声学贡献法分析了车身顶棚不同区域板件的振动对车内噪声的 贡献,在贡献较大的区域设计了具有双带隙和点缺陷的声子晶体结构.利用双振子声子晶体的双重局域共振带隙 特性降低正贡献区域噪声,同时点缺陷带隙特性避免负贡献区振动的衰减.结果表明,设计的声子晶体结构对降低 车内噪声具有良好的效果.
In order to reduce the interior noise of vehicle at medium-low frequencies,the contributions of vibrations of panels in the different areas of car roof to the interior noise of vehicle are analyzed l)y using panel a-coustic contribution method,and in the areas with larger acoustic contribution, the phonon crystal structures with dual band gaps and point defects are designed. The characteristics of dual locally resonant band gaps are conducive o the noise reduction in positive contribution areas while that of point defects help avoid vibration attenuation in negative contribution areas. The results show that the phonon crystal structures designed have good effects on the re-duction of interior noise.