Dynamical landscape of transitional pipe flow.
Dynamical landscape of transitional pipe flow.
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过渡管流的动态景观。
DOI：
10.1103/physreve.105.045108
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发表时间：
2022
期刊：
影响因子：
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通讯作者：
Frishman A
中科院分区：
文献类型：
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作者：
Frishman A
管内向湍流过渡的特点是层流态和湍流态共存。在跃迁的下端，可以激发局部的湍流脉冲，称为喷雾。当罕见的涨落使喷雾接近位于层流相空间边界的边缘状态时，喷雾就会衰变。在较高的雷诺数下，均匀湍流可以持续，并且在层流流动中占主导地位。在这里，我们完成了这幅定域态的图景，把它放在一个统一的分叉图中。我们在巴克利模型中展示了我们的主张，并对它们进行了一般激励。具体地说，我们建议存在一个反吹气态和一个反映气泡及其相关边态的带隙边态。先前观察到的在均匀湍流中形成的层流缝隙被自然地识别为通过缝隙边缘成核和衰减的反喷气。我们还讨论了所建议的分叉图的替代方案，该分叉图可能与直管以外的壁面边界流有关。
The transition to turbulence in pipes is characterized by a coexistence of laminar and turbulent states. At the lower end of the transition, localized turbulent pulses, called puffs, can be excited. Puffs can decay when rare fluctuations drive them close to an edge state lying at the phase-space boundary with laminar flow. At higher Reynolds numbers, homogeneous turbulence can be sustained, and dominates over laminar flow. Here we complete this landscape of localized states, placing it within a unified bifurcation picture. We demonstrate our claims within the Barkley model, and motivate them generally. Specifically, we suggest the existence of an antipuff and a gap-edge—states which mirror the puff and related edge state. Previously observed laminar gaps forming within homogeneous turbulence are then naturally identified as antipuffs nucleating and decaying through the gap edge. We also discuss alternatives to the suggested bifurcation diagram, which could be relevant for wall-bounded flows other than straight pipes.
影响因子：
56.9
作者：
V. Gates;.. M. L. Ludwig-M.-L.-Ludwig-2273875465;J. A. Hartsuck;T. A. Steitz;H. Muirhead;J. C. Coppola;G. N. Reeke
通讯作者：
V. Gates;.. M. L. Ludwig-M.-L.-Ludwig-2273875465;J. A. Hartsuck;T. A. Steitz;H. Muirhead;J. C. Coppola;G. N. Reeke
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