在流中逆流和外游的预测框架.
1Department of Mechanical Engineering, <a href="https://ror.org/04dese585">Indian Institute of Science</a>, Bengaluru, India.
Physical review letters
|October 25, 2024
概括
本研究引入了一个动态框架,以了解流循环中的间歇性反转和外出. 它表明这些事件源于不稳定的周期轨道,使得极端流动波动的预测和控制成为可能.
科学领域:
- 流体动力学 流体动力学
- 流理论是关于流的.
- 动态系统是动态系统.
背景情况:
- 在动荡的大型循环中,会出现间歇性的反转和外出 (R&E).
- 了解这些极端事件的潜在机制对于预测和控制流至关重要.
研究的目的:
- 提出一种新的动态框架,用于分析动荡流中的间歇性反转和异常 (R&E).
- 展示如何利用动态系统理论的见解来预测和控制R&E.
主要方法:
- 开发基于相位空间轨迹和不变的多元体的动态框架.
- 利用不稳定的周期轨道 (UPO) 和它们的相关多元体来重建流动力学.
- 实施闭环控制策略,以预防性地避免极端事件.
主要成果:
- 当流轨迹阴影特定不稳定周期轨道 (UPOs) 的不变多元体时,R&Es就会发生.
- 在R&E期间的流量重组和极端波动可以通过将动态相关的UPO的不稳定分组拼接重建.
- 该框架可以预测即将发生的R&E.
结论:
- 几何动态框架为流中间歇性极端事件提供了新的视角.
- 预测能力允许对R&E进行先发制人的控制,为管理流系统提供了潜在的应用.
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