在平面Couette流中同临床的分叉和边缘状态的切换
Julius Rhoan T Lustro1,2, Yudai Shimizu2,3, Genta Kawahara2
1Department of Mechanical Engineering, University of the Philippines Diliman, Magsaysay Avenue, Diliman, Quezon City, Metro Manila 1101, Philippines.
Chaos (Woodbury, N.Y.)
|June 5, 2023
概括
同性临床分叉揭示了新的时间周期解决方案和平面Couette流中的边缘状态. 这些发现增强了对围墙切割流中的亚临界过渡到流的理解.
科学领域:
- 流体动力学 流体动力学
- 非线性动力学是一种非线性动力学.
- 计算物理 计算物理
背景情况:
- 在围墙切割流中,亚临界过渡到流是一个复杂的现象.
- 边缘状态,代表不变的解决方案,在理解这种过渡中起着至关重要的作用.
- 之前的研究已经探索了各种机制,但完整的画面仍然难以捉摸.
研究的目的:
- 为了确定与边缘状态相关的同临床分叉,在由纳维埃-斯托克斯方程控制的平面库埃特流中.
- 调查新的周期性解决方案的出现及其与现有的稳定解决方案的关系.
- 阐明这些分叉和边缘状态在过渡到流中的作用.
主要方法:
- 在平面 Couette 流配置中,对 Navier-Stokes 方程的数值模拟.
- 对分叉场景的分析,重点关注同临床分叉.
- 时间周期解决方案 (PO3) 和稳定解决方案 (Nagata) 的识别和表征.
主要成果:
- 确定了三个同临床分支,与平面Couette流中的边缘状态有关.
- 发现新的时间周期解决方案 (PO3) 和纳加塔稳定解决方案作为边缘状态.
- 从Nagata溶液切换到PO3的边缘状态在较高的雷诺兹数中被观察到,这是由于同临床分叉.
结论:
- 同类临床分叉是创造/破坏时间周期解决方案和影响边缘状态的关键机制.
- 观察到的边缘状态切换会影响盆地边界,改变过渡动态.
- 这项研究提供了对驱动流中流过渡的基本机制的见解.
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