动荡的不稳定性推动了极端集群
F Zapata1,2, S Angriman1,2, A Ferran3,4
1Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Física, Ciudad Universitaria, 1428 Buenos Aires, Argentina.
Physical review letters
|March 22, 2024
概括
流不稳定性显著影响粒子聚类. 这项研究揭示了由于不稳定的动荡而导致自然流的极端聚类,超过了平均效应的预测.
科学领域:
- 流体动力学 流体动力学
- 流的研究研究.
- 带有颗粒物的流动.
背景情况:
- 动荡通常被研究为稳定状态现象.
- 在流中粒子聚类是研究的一个关键领域.
- 流不稳定对粒子行为的影响尚未完全理解.
研究的目的:
- 为了研究不稳定的流对粒子聚类的影响.
- 为了确定流量参数和粒子集群形成之间的相关性.
- 为观察到的相关性提供一个维度论证.
主要方法:
- 使用了直接的数值模拟 (DNS).
- 一个稳定的强迫产生了一个不稳定的大规模流.
- 分析的重点是即时流参数和粒子聚类.
主要成果:
- 流不稳定性极大地影响了流参数和粒子聚类.
- 粒子聚类与即时的基于泰勒的流量雷诺斯数相关.
- 粒子聚类与即时流能量消散常数有反相关性.
结论:
- 动荡中的不稳定性是粒子集群形成的关键因素.
- 在自然不稳定的流动中,极端粒子聚类可能发生.
- 观察到的聚类比平均惯性流效应预测的要明显.
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