浅海声速剖面和沉积层对低频声传播损失的影响

Effect of sound velocity profile and sediment on low frequency sound transmission loss in shallow water

基于波数积分方法,针对浅海3种典型声速剖面和细砂、粉砂及黏土-粉砂3种沉积层,利用快速场程序得到低频声在近程和远程的传播损失。数值结果表明:声速剖面在近距离上对传播损失没有显著影响,远距离上负梯度、负跃层分布时的传播损失明显高于等声速分布的传播损失;沉积层在近距离和远距离对传播损失都有较明显的影响,远距离时沉积层的衰减系数起重要作用。

Base on the wave-number integration method and the fast field program, the transmission loss, which is about fine sand、silt and clayey-silt bottom sediment and three kinds of sound speed profile in shallow water, is calculated in short and long distance. As illustrated by numerical simulations, the sound speed profile has no significant influence on transmission loss at close range. The transmission loss of the shallow water with negative gradient and negative thermocline over long distance is obviously higher than that of equal sound speed profile. The sediment in shallow water has an obvious influence on the transmission loss in short and long distance.The attenuation coefficient of the sediment play an important role in long distance.