活跃强度和停滞点奇点在浅处的水下波导中
Peter H Dahl1, David R Dall'Osto1, William S Hodgkiss2
1Applied Physics Laboratory, University of Washington, Seattle, Washington 98105, USA.
The Journal of the Acoustical Society of America
|September 11, 2023
概括
使用矢量声学研究了水下声学的区域. 观测和建模显示,由于沉积物减弱,这些区域因范围而变深,证实了理论预测.
科学领域:
- 海洋声学 海洋声学
- 水下声学 水下声学
- 地声学是地球声学.
背景情况:
- 水下波导中的声场表现出由源特性和环境因素影响的复杂性质.
- 了解声学强度模式,包括区域,对于声学传播建模至关重要.
研究的目的:
- 为了研究一个窄带声场的矢量声学特性作为范围的函数.
- 为了研究活跃声学强度的旋区域和单一点.
- 将观测数据与基于正常模式和地声模型的解释性建模进行比较.
主要方法:
- 使用在浅水波导中的拖动源测量载体声学特性.
- 对声压和速度数据的分析,包括波数谱的逆汉克尔变换.
- 将观察到的数据与使用地球声学配置文件的正常模式模型进行比较.
主要成果:
- 三种被困模式在43Hz时得到支持,模式2被微弱激发.
- 确定了带有奇点 (和停滞点) 的旋转区域.
- 模型与数据的比较显示出一致性,证实了状区域的特性.
- 观测和建模都表明,随着范围的增加,旋区域的逐渐深化.
结论:
- 矢量声学为水下声场特性提供了宝贵的见解.
- 这项研究证实了在浅水环境中存在声区域的存在和行为.
- 沉积物衰减在观察到的 vortex 区域深化中发挥着重要作用.
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