在滑动的不对称凸起上凝结
Kyoo-Chul Park1,2, Philseok Kim2, Alison Grinthal1
1John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts, USA.
Nature
|February 25, 2016
概括
这项研究引入了一种新的仿生表面设计,用于有效控制水滴凝结. 新的表面协同增强水滴的生长和快速流失, 优于现有的水收集和热传输技术.
科学领域:
- 表面科学和材料工程
- 仿生学和纳米技术
- 流体动力学和热传递
背景情况:
- 控制液滴凝结对于收集水,淡化和热管理至关重要.
- 现有的微/纳米尺度表面纹理面临着液滴生长和传输之间的权衡.
- 自然设计提供了克服这些限制的可能性.
研究的目的:
- 开发一种新的表面设计,以协同控制凝结过程中滴滴的生长和快速流失.
- 研究沙漠甲虫,仙人掌和植物的仿生原理,以提高凝结性能.
- 优化表面的几何和化学结构,以便有效地收集和运输水.
主要方法:
- 在优化凸凸点上的蒸汽扩散流的理论建模.
- 整合仿生特征:以甲虫为灵感的顶部几何,以仙人掌为灵感的斜坡,以及以植物为灵感的纳米涂层.
- 在设计的表面上对凝结,滴滴生长和传输进行实验性描述.
主要成果:
- 优化的毫米凸起具有特定的曲率和形状最大化蒸汽扩散.
- 通过自由能源配置实现促进增长和定向运输的协同作用.
- 与合成表面相比,仿生表面显示出明显增强的液滴增长率,更快的开始,更高的周转率和更大的水收集率.
- 观察到有效的滴体运输和不利的温度梯度.
结论:
- 一个概念上新的,仿生设计策略显著增强了凝结控制.
- 合理设计的表面在水收集和相变热传输方面优于现有技术.
- 这种方法为开发高效的水资源管理和热系统提供了途径.
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