在固体圆柱形表面上滴滴的下降角度的几何依赖
Mingzhu Cui1, Anthony D Dinsmore1
1Physics Department, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States.
Langmuir : the ACS journal of surfaces and colloids
|April 21, 2025
概括
水表面上水滴的退缩接触角度随着基板曲率的变化而变化,这与之前的假设相反. 这一发现影响了滴水的行为,并对设计水面进行水管理产生了影响.
科学领域:
- 表面科学与工程 表面科学与工程
- 湿度和接触角现象 湿度和接触角现象
- 表面上的流体动力学.
背景情况:
- 固体上的部分湿滴表现出接触角度歇斯底里.
- 下降 (θR) 和前进 (θA) 的接触角度通常被认为是特定于材料的.
- 基板几何学对这些参数的影响尚未得到充分证实.
研究的目的:
- 为了研究基板曲率对水滴接触角度的影响.
- 要确定退缩接触角 (θR) 是否取决于几何.
- 了解几何依赖性歇斯底里对滴滴行为的影响.
主要方法:
- 测量了PDMS功能化玻璃上的水滴接触角度,曲率不同 (直径平到2毫米的杆).
- 量化后退和前进的接触角度 (θR, θA).
- 分析了倾斜的杆子上的滴滴退缩速度和滑动行为.
主要成果:
- 潜入接触角度 (θR) 与基板曲率 (86.0°在平面上到95.6°在2mm棒上) 有显著差异.
- 前进的接触角度 (θA) 保持不变 (103.2°),独立于几何形状.
- 滴滴滑动角度在曲面上较低,在曲面上具有较小的hysteresis.
结论:
- 接触角歇斯底里斯受基质曲率和滴滴形状的影响.
- 接触线运动的能量屏障取决于几何.
- 这些发现使得量身定制的表面设计能够在自清洁和收集水等应用中进行滴滴操纵.
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