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Updated: Jan 8, 2026

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不单调的扩散在剪切的活跃悬浮中的squirmers
Zhouyang Ge1,2, John F Brady3, Gwynn J Elfring1
1University of British Columbia, Department of Mechanical Engineering and Institute of Applied Mathematics, Vancouver V6T 1Z4, British Columbia, Canada.
Physical review letters
|December 19, 2025
概括
剪切流令人惊地减缓了悬浮中的活性颗粒扩散. 这种非单调的扩散源于持续运动和剪切效应之间的相互作用,为控制活性流体中的运输提供了新的方法.
科学领域:
- 软物质物理学 软物质物理学
- 流体动力学 流体动力学
- 活动物质 活动物质
背景情况:
- 悬浮中的活性颗粒表现出由内部推进和外部力量影响的复杂动力学.
- 了解切割对活性物质的影响对于微流体学和材料科学中的应用至关重要.
研究的目的:
- 研究剪切速率对悬浮中的活性颗粒扩散动态的影响.
- 阐明活动诱导运动和剪切诱导对粒子传输的影响之间的相互作用.
主要方法:
- 使用无极活性悬浮的squirmers作为模型系统.
- 执行具有可调节持久性的自行粒子模拟.
主要成果:
- 观察到一个非单调的,减缓了长期的扩散动态随着剪切率的增加.
- 证明这种现象是由持续运动和剪切诱导的重定位/扩散的合引起的.
- 证实了在具有微观结构和持久性的活性流体中非单调扩散的普遍性.
结论:
- 剪切对活性悬浮的扩散有非线性影响.
- 内部活动和外部强迫相互作用以调节粒子运输.
- 这些发现为控制活性流体中运输现象提供了新的策略.
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