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惯性驱动游泳者悬挂中的度波动
Purnima Jain1, Navdeep Rana2, Sriram Ramaswamy3,4
1<a href="https://ror.org/03ht1xw27">Tata Institute of Fundamental Research</a>, 36/P, Gopanpally Village, Serilingampally Mandal, Ranga Reddy District, Hyderabad 500046, Telangana, India.
Physical review letters
|October 25, 2024
概括
我们在自动运动粒子悬浮中发现了一种新的不稳定性. 这种现象是由惯性,运动性和度波动引起的,导致自我维持的波浪和活跃的流.
科学领域:
- 物理 物理学 物理
- 流体动力学 流体动力学
- 统计力学 统计力学
背景情况:
- 活性物质系统,就像自动运动粒子的悬浮一样,表现出复杂的行为.
- 了解这些系统中模式形成和流背后的驱动力至关重要.
研究的目的:
- 确定和描述自行运动粒子悬浮中的一种新型不稳定机制.
- 探索这些系统从常规振荡过渡到活跃流的过程.
主要方法:
- 高分辨率的数值模拟自行推进的粒子悬浮.
- 对新出现的活跃流的统计特征的分析.
主要成果:
- 发现一种不稳定机制不是由活跃应力驱动,而是由惯性,运动性和度波动驱动.
- 观察速度和度场之间的时间滞后导致不稳定.
- 集中和定向的自持波的表征,过渡到波动的波动.
- 确定活跃流与被动标量体的巴切勒光谱之间的联系.
结论:
- 已经确定了自动粒子系统中激活流的新途径.
- 惯性,运动性和度波动的相互作用是这种现象的关键.
- 这些发现为积极物质的统计力学提供了洞察力.
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