微流体网络中的Braess悖论和可编程行为
Daniel J Case1, Yifan Liu2, István Z Kiss2
1Department of Physics and Astronomy, Northwestern University, Evanston, IL, USA.
Nature
|October 25, 2019
概括
研究人员设计了具有非线性流动行为的新型微流体网络. 这项创新使微流体设备的集成控制成为可能,为先进的便携式系统铺平了道路.
科学领域:
- 流体动力学
- 微流体学
- 非线性系统
背景情况:
- 由于线性流动,微流体系统需要外部控制装置.
- 缺乏综合控制阻碍了复杂的微流体应用的发展.
研究的目的:
- 设计具有非线性压力-流量关系的微流体网络.
- 通过操纵输入/输出压力来实现集成流量控制.
主要方法:
- 使用刚性聚合物通道实现微流体网络.
- 在不同压力下对水流动的实验研究.
- 分析流动行为类似于布雷斯悖论.
主要成果:
- 在微流体网络中证明了非线性压力流量关系.
- 观察到布雷斯悖论的流体类比:关闭通道增加了总流量.
- 用多个交换机展示可扩展的流程路由功能.
结论:
- 非线性微流体网络为集成控制机制提供了途径.
- 在医疗保健和太空探索方面开发先进的便携式系统的潜力.
- 促进了需要复杂的微观流体操纵的新应用.
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