通过移动战线过渡到流的阶段过渡
Sébastien Gomé1,2, Aliénor Rivière1, Laurette S Tuckerman1
1Laboratoire de <a href="https://ror.org/03kr50w79">Physique et Mécanique des Milieux Hétérogènes</a>, CNRS, ESPCI Paris, PSL Research University, Sorbonne Université, Université Paris-Cité, Paris 75005, France.
Physical review letters
|July 12, 2024
概括
亚临界流中的流在平面Couette流中发生的转变不同,没有离散结构. 这项研究揭示了一个更简单的前沿扩张和层状区域衰变的场景,映射到一个随机系统.
科学领域:
- 流体动力学 流体动力学
- 流是什么?流是什么?流是什么?
- 阶段过渡 阶段过渡
背景情况:
- 定向透 (DP) 是连续相变的普遍性类.
- DP已与亚临界壁边界流动中的流有关.
- 规范流体表现出离散的流结构 (气泡/波段),可以自我复制或分层化.
研究的目的:
- 研究在亚临界剪切流中流过渡的普遍性.
- 探索平面Couette流中的离散结构之外的过渡机制.
- 将观察到的过渡映射到一个随机系统上.
主要方法:
- 数字实验旨在消除平面Couette流中的离散流结构.
- 分析了通过扩展前线的流扩散和通过层状区域的形成的衰变.
- 将相位过渡映射到一个随机单变量系统.
主要成果:
- 平面库埃特流表现出比规范流更简单的过渡场景,没有离散结构.
- 流通过膨胀的前线扩散,并通过自发的层状区域形成而衰变.
- 过渡的性质 (不连续或DP类连续) 取决于动波动水平.
结论:
- 平面库埃特流中的过渡机制不同于正规管道和平面流.
- 这一发现挑战了离散结构介导的流过渡的普遍性.
- 这些结果对理解各种水力动力学系统中的流有重大影响.
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