利用解析法研究相同底质水域中点声源随深度传播规律

Using analytical method to study the propagation of point sound source in water field with uniform floor

浅海波导的传播环境主要由海底和海面构成,声波在浅海波导内的传播衰减规律可以利用简化的相同底质的平行界面内声波的传播模型研究。本文利用解析法研究了浅海条件下相同底质水域中点声源的传播衰减规律,进行了平行介质内球面波的简正波分解,推导给出下表面为刚性、上表面为绝对软情况下简正波的衰减规律。分析了简正波和侧面波引起的声场;仿真计算了平行介质层中定深点声源传播的简正波和侧面波,给出相应的传播规律结论。本研究对理解浅海条件下舰船辐射噪声信号的传播衰减规律和舰船辐射噪声的量级评价具有一定的指导意义。

Sea surface and bottom constitute shallow sea waveguide＇s propogation enviroment.The propagation of sound wave in shallow sea waveguide can be studied using a simplified model with paralell interfaces and a uniform bottom.In this paper,we used analytical method to study the propagation of point sound source in shallow water with uniform floor.At first,we decomposed spherical wave of the spot sound source into a series of normal modes between parallel boundaries.Then we discussed the propagation attenuation of normal modes in assumption that the bottom is rigid and the upper surface is absolute soft.We analyzed the sound filed caused by the normal mode and side wave,simulated the normal mode and side wave in parallel layers,and finally gave the conclusion.Our study will be helpful in understanding the propagation of ship noise in shallow sea inviroment and assessing the level of it.