微游泳器通过内部散射产生最小的.
Abdallah Daddi-Moussa-Ider1, Ramin Golestanian1,2, Andrej Vilfan3,4
1Max Planck Institute for Dynamics and Self-Organization (MPI-DS), 37077, Göttingen, Germany.
Nature communications
|September 28, 2023
概括
与被动粒子相比,自行式微游泳器具有独特的能量消散和产生. 一个新的定理确定了微游泳者消散的下限,揭示了活跃游泳者的明显基本极限.
科学领域:
- 物理 物理学 物理
- 软物质物理学 软物质物理学
- 流体动力学 流体动力学
背景情况:
- 与外部驱动的被动粒子相比,自行式微游泳器表现出明显的能量消耗和产生机制.
- 微游泳器的流场和内部推进机制与被动系统有很大的不同.
研究的目的:
- 推导出一个一般定理,为微游泳器的总能耗 (外部和内部) 提供一个精确的下界.
- 为了研究游泳者的形状如何影响在恒定体积下总消散.
- 为了比较活跃与被动系统中产生的基本极限.
主要方法:
- 微游泳者消散的一般理论框架的推导.
- 该定理应用于特定的微游泳模型,包括表面推进的水滴和带有延伸推进层的游泳者.
- 对游泳者形状的分析,以尽量减少总消散.
主要成果:
- 建立了一个一般定理,为微游泳器的总消散产生一个精确的下界.
- 该定理适用于各种微游泳类型,包括活跃滴和具有内部散射的游泳者.
- 分析揭示了最佳的游泳者形状,以最大限度地减少在恒定体积下消散.
- 在活跃的微游泳者中,的产生被不同的基本极限所支配.
结论:
- 衍生定理提供了一种普遍的方法来量化微游泳器能量消耗.
- 与被动粒子相比,活跃的微游泳体面临着不同的热力学约束.
- 了解这些限制对于设计高效的微观人工游泳器至关重要.
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