孤子内波对声场水平纵向相干特性的影响

Effects of solitary internal wave on horizontal longitudinal coherence of shallow-water acoustic fields

运用抛物方程计算模型,研究了浅海孤子内波对声场水平纵向相干特性的影响。仿真结果表明,孤子内波会引起水平纵向相关系数随时间出现起伏。起伏的幅度与收发深度有关,起伏周期与孤子内波的传播速度有关。理论分析给出了在孤子内波的传播方向与水平阵平行时,水平纵向相关系数随时间变化的简明表达式。

A numerical study of the effect of a solitary internal wave on the horizontal longitudinal coherence in a shallow water waveguide with a thermocline is carried out based on parabolic equation （PE） model. The result shows that the horizontal longitudinal correlation coefficient oscillates with time. The amplitude of oscillation is related to the depth of receiver and source, and the period of oscillation is related to the propagation velocity of solitary internal wave. A simple expression of the relation between horizontal longitudinal coherence and time is theoretically derived for the case that the propagation direction of solitary internal wave is parallel to the array.