公路隧道内主动降噪声源布置位置仿真模拟

Analogue simulation of the active noise control source location in highway tunnel

基于声波干涉原理对高速公路隧道内噪声的主动降噪特性进行了理论分析,采用有限元法建立了3条隧道全尺寸断面模型,计算得出隧道内声压级分布,分析了主动降噪时的隧道内声场特性.考虑噪声声源频率的差异,噪声频率越低,隧道内主动降噪效果越好;考虑主动降噪设备位置的不同,将主动声源与噪声源、降噪点的空间距离加和,再与噪声源与降噪点的空间距离作比较,若两者差值为噪声波长的整数倍,则可在降噪点附近实现3dB以上区域降噪.

The active noise reduction feature of highway tunnel is analyzed theoretically based on the principle of acoustic interference.The models of three full-sized tunnels are established based on finite element method（FEM）.The distributions of sound pressure level are calculated,and the characteristics of sound field in tunnels are analyzed during active noise cancellation.The results show that the lower the noise frequency is,the better the effect of active noise control is when adding the spatial distance between the active noise control device and the noise source to the spatial distance between the active noise control device and the noise reduction position,getting a sum,then comparing the sum and the spatial distance between the noise source and the noise reduction position,there is a conclusion that if the difference value is the integral multiples of noise wavelength,noise reduction of more than 3dB can be achieved nearby the noise reduction area.