控制到活跃流的路线:用拓缺陷填充一个活动点
Arghavan Partovifard1, Holger Stark1
1Division of Theoretical Physics, Institute of Physics and Astronomy, Technische Universität Berlin, Hardenbergstr. 36, D-10623 Berlin, Germany. arghavan.partovifard@campus.tu-berlin.de.
Soft matter
|February 24, 2026
概括
我们展示了如何控制棒的液体悬浮中的活跃流. 增加流体中活跃点的大小会导致缺陷形成,最终导致混乱的流.
科学领域:
- 软物质物理学 软物质物理学
- 活体物质系统是什么
- 流体动力学 流体动力学
背景情况:
- 活性物质系统,就像杆的悬浮一样,表现出由内部能量来源驱动的复杂行为.
- 螺母秩序是杆状分子的常见属性,可以受到外部活动的影响或诱导.
- 活性流是一种在某些活性物质系统中观察到的混乱状态,其特点是旋转的流动模式和拓缺陷.
研究的目的:
- 建立一种可控的方法,以诱导活跃超神经流体中的活跃流.
- 调查活跃点的尺寸和边界对流过渡的影响.
- 描述在活跃流开始时的拓缺陷和流动模式的动态.
主要方法:
- 在棒的被动液体悬浮中引入一个具有非零活动的圆形点.
- 系统地改变活动点半径 (r) 以观察流体行为的变化.
- 分析拓缺陷动力学 (电荷,入口,运动) 和流动特征 (内流,利亚普诺夫指数).
主要成果:
- 随着点半径的增加,超神态顺序转换为暂时的,然后是稳定的拓缺陷 (+1⁄2电荷).
- 缺陷电荷积累与斑点的边缘活动和活跃的长度尺度有关.
- 截然不同的动态模式,标志着静态和利亚普诺夫指数的急剧增加,在大量活跃动荡之前.
结论:
- 通过增加嵌入式活性点的半径来实现对活跃流的受控路径.
- 活动流,边界条件和缺陷动态之间的相互作用决定了过渡到流的过程.
- 这项研究提供了对活跃阴性系统中缺陷生成和混乱行为的洞察.
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