由随机平均流量诱导的快慢波过渡
S Boury1, O Bühler1, J Shatah1
1Courant Institute of Mathematical Sciences, New York University, New York, New York 10012, USA.
Physical review. E
|December 20, 2023
概括
随机流中的分散波可以从快速转变为缓慢,改变它们的行为. 这种过渡取决于波浪特性和流动动力学,特别是不稳定的流.
科学领域:
- 流体动力学 流体动力学
- 大气-海洋系统.
- 波浪的传播方式
背景情况:
- 最近对大气-海洋流体动力学的非对称结果.
- 了解复杂流中的波浪行为至关重要.
研究的目的:
- 研究分散波中群速变化的条件.
- 分析由于多普勒转移和折射而导致的快速-缓慢波转变.
主要方法:
- 理想化的数值和理论研究.
- 在随机平均流量中分析二维分散波.
主要成果:
- 对快慢转换的分散关系和平均流动幅度的确定条件.
- 为稳定的平均流量确定了有限的振幅值.
- 表明不稳定的流动可以驱动不论幅度的过渡.
结论:
- 快速-缓慢波转换是可能的,并且取决于流动特征.
- 不稳定的流量显著影响波浪行为和长期命运.
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