在充满活性流体的狭窄方形域中的粒子运动上
Hao Ye1, Zhenyu Ouyang2, Jianzhong Lin1,2
1Department of Mechanics, State Key Laboratory of Fluid Power and Mechatronic Systems, Zhejiang University, 310027 Hangzhou, China. mecjzlin@public.zju.edu.cn.
Soft matter
|February 2, 2024
概括
活体流体中的被动粒子表现出基于限制的独特行为. 强大的束将粒子驱动到中心或角落,而弱的束显示出边界增强的相关性和减少的结构形成.
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:
- 活性流体表现出复杂的粒子动态.
- 限制会显著改变流体中的粒子行为.
- 对各种应用来说,了解受限活性流体中的粒子运动至关重要.
研究的目的:
- 以数值模拟被动粒子在充满活性流体的封闭方形域中的运动.
- 研究不同程度的限制 (强或弱) 对粒子动态的影响.
- 分析不同活动水平下的粒子的集体行为和相关性.
主要方法:
- 数字模拟的直接虚构域方法.
- 基于粒子直径与域边长比率 (dp/L) 的限制的分类.
- 对转换平均平方位移 (MSD_T),辐射概率密度和角速度的分析.
主要成果:
- 弱封闭粒子显示时间依赖的MSD_T,由于封闭而达到平原.
- 在高活动水平时,粒子位置集中在边界和角落附近.
- 强烈受限的粒子在旋转时向中心或角落迁移.
- 在角速度中的局部最小值显示了的周期性组织.
- 两个不同的模式将粒子旋转速度与活动相关联.
- 与无界流相比,切线长度 (Rc) 和空间相关性 (Rp) 较小,这表明受限对结构形成的影响.
结论:
- 边界限制显著影响活性流体中的粒子动力学和集体行为.
- 限制的程度决定了粒子迁移模式和位置分布.
- 与无界流相比,封闭抑制了连贯结构的形成.
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