由两个波系统触发的水力动力学调制不稳定性
Yuchen He1,2, Jinghua Wang1,3,4, Bertrand Kibler5
1Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong 999077, China.
Chaos (Woodbury, N.Y.)
|October 2, 2024
概括
深水波中的调制不稳定性 (MI) 可以通过两波过程触发,而不仅仅是传统的三波系统. 这一发现影响了对流波形成和波列车演变的理解.
科学领域:
- 流体动力学 流体动力学
- 非线性物理学 非线性物理学
- 海洋学 海洋学 海洋学
背景情况:
- 调制不稳定性 (MI) 驱动波列瓦解和流波形成.
- 一次性心脏病通常由一个包含载波和两个侧带的三波系统启动.
- 之前的研究探讨了MI在各种非线性分散介质中.
研究的目的:
- 在深水表面重力波中实验性地研究MI.
- 要确定MI是否可以通过更简单的两波过程触发.
- 用先进的数值模拟来验证实验发现.
主要方法:
- 对深水表面重力波的实验研究.
- 使用单个不稳定的侧带和峰值频率 (两波过程) 启动MI.
- 使用完全非线性水力动力学数值波模拟的验证.
主要成果:
- 证明MI可以通过深水波中的两波过程触发.
- 实验数据与数值模拟显示出极好的一致性.
- 在长期进化过程中观察到费米-帕斯塔-乌拉姆-辛古聚焦周期的明显转变.
结论:
- 经典理解MI启动被扩展到包括一个两波过程.
- 这项研究为流波生成机制提供了新的见解.
- 这些发现有助于理解非线性波动力学及其长期演变.
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