噪声吸声结构体特性  

The characteristics of the noise absorber

作　　者：徐春龙[1] 王晋国[1] 王静云[1] 常安定[1] 

机构地区：[1]长安大学理学院,陕西西安710064

出　　处：《西北大学学报（自然科学版）》2013年第6期898-902,共5页Journal of Northwest University（Natural Science Edition）

基　　金：陕西省科技攻关计划基金资助项目(2012K09-07);中央高校基本科研业务费基金资助项目(2013G1121085)

摘　　要：为了研究噪声吸声结构体的吸声特性,基于声波的传播理论,建立了声波三维空间反射模型,利用Matlab编程进行数值模拟,分析了声波反射次数及反射功率与劈尖型吸波体几何参数之间的关系。研究结果表明,声波反射次数与劈尖的高度无关;劈尖体的夹角越小反射次数越大,而最终的反射功率越小;劈尖体的高度影响吸波体的低频吸收效果。考虑到实际加工条件,参考轨道交通噪声的低限频率,劈尖夹角为10度左右,高度确定在0.243 5~0.340 4 m之间对交通噪声的降噪效果最佳。In order to study the characteristics of the noise absorber, based on the theories of acoustic propagation, the 3 D reflection model is set up. The relations between the physical dimension, the reflection times and the reflect power is analyzed, with the help of the Matlab. The results show that the reflection time of sound wa^es are irrele- vant to the height of wedge. The smaller the angle of wedge is, the fewer number the reflection time will become, but the reflected power will get even smaller. The height of wedge influences the absorption effect on low frequency sound. On the basis of the research results, with reference to the actual processing conditions and the low limited frequency of the traffic noise, the angle of wedge should be fixed at 10 degree. In order to achieve the best effect of noise absorption, the height of wedge should range from 0.243 5 to 0. 340 4 meter.

关 键 词：劈尖夹角 劈尖高度 反射次数 反射波功率 

分 类 号：O422.4[理学—声学]