一种明确的颗粒力学方法来研究海洋沉积物声学
Abram H Clark1, Derek R Olson2, Andrew J Swartz1
1Physics Department, Naval Postgraduate School, Monterey, California 99343, USA.
The Journal of the Acoustical Society of America
|May 29, 2024
概括
颗粒力学揭示了沉积物结构如何影响声波速度和衰减. 无序的颗粒包装表现出独特的缩放规律,对沉积物声学至关重要,挑战连续模型.
科学领域:
- 地质物理学 地质物理学
- 声学 声学 在声学上
- 颗粒物理 颗粒物理
背景情况:
- 海洋沉积物声学模型经常使用连续性近似.
- 这些模型可能无法完全捕捉颗粒物质内部的复杂相互作用.
- 了解沉积物中依赖频率的声音传播对于地质物理应用至关重要.
研究的目的:
- 用颗粒力学研究海洋沉积物中相速和衰减的频率依赖性.
- 探索颗粒包装结构在沉积物声学中的作用.
- 为沉积物声学特性开发一个更完整的理论框架.
主要方法:
- 基于颗粒力学原理的理论研究.
- 使用离散元件方法 (DEM) 模拟的计算分析.
- 模拟颗粒物质作为具有双相接触力 (排斥力和消散力) 的离散物体.
主要成果:
- 无序的颗粒包装对频率依赖的相速和衰减表现出异常的缩放规律.
- 这些缩放规律偏离了连续性治疗的预测.
- 颗粒状包装结构显著影响沉积物的声学特性.
结论:
- 颗粒状包装结构是沉积物声学的一个关键因素,在当前的模型中经常被忽视.
- 颗粒力学方法为了解沉积物声学行为的新视角提供了新的视角.
- 这项研究作为未来模型的基础,包括流体动力学和惯性效应.
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