随机步行模型用于波动流中的双级
1Courant Institute of Mathematical Sciences, New York University, New York, New York 10012, USA.
Physical review. E
|June 22, 2024
概括
水力动力学和波浪流表现出明显的双级联. 波动流显示出大量的流量波动,由随机步行模型解释,这表明这些光谱流动是由偶然而不是不可逆转的动力驱动的.
科学领域:
- 物理 物理学 物理
- 流体动力学 流体动力学
- 非线性系统是非线性系统.
背景情况:
- 双级联,涉及两个保存的二次数量,在2D水力动力学流和波浪流中观察到.
- 波动流的例子包括表面波和具有立方体非线性非线性施罗丁格方程.
研究的目的:
- 为了比较双级联的物理性质在2D水力动力学流和1D波动流.
- 调查在它们的光谱流和波动中观察到的明显差异背后的原因.
主要方法:
- 对于二维水力动力学流和一维波系统的强迫分散平衡的数值模拟.
- 在惯性范围内比较能量光谱,分析时间流动波动.
- 为波动流双级制定和测试一个随机步行模型.
主要成果:
- 在水力动力和波动流之间的光谱和时间流动波动中发现了显著的差异.
- 波动流表现出更大的流量波动,包括信号逆转,缺少在水力动力学流.
- 一个随机步行模型成功地复制了观察到的乱光谱,并解释了波浪乱中的大流量波动.
结论:
- 波动流中的双级联不需要不可逆转的动态机制.
- 在波动流中观察到的光谱流可以由随机机会引起,随机步行模型证明了这一点.
- 非线性扩散模型无法解释波动流中观察到的光谱形状.
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