在结构化超水表面的亚亚巴特切割流中保持和离开掉落
Blake M Lyons1, Daniel Maynes1, Julie Crockett1
1Department of Mechanical Engineering, Brigham Young University, Provo, Utah 84604, United States.
Langmuir : the ACS journal of surfaces and colloids
|August 24, 2024
概括
超疏水表面降低了滴滴离开所需的剪切流速. 较低的表面固体分数显著降低了去除滴滴所需的空气速度,表明增强了移动性.
科学领域:
- 表面科学是一门科学.
- 流体动力学 流体动力学
- 材料科学 是一种材料科学.
背景情况:
- 滴滴在表面上的保留是由表面张力,滴滴几何形状和接触角度决定的.
- 外在力量超过保留力启动滴滴运动.
- 了解滴滴偏离对于涉及对表面流体操纵的应用至关重要.
研究的目的:
- 在施加剪切流下,研究结构化超水表面上的滴滴偏离条件.
- 分析表面微观结构和固体部分对液滴流动性的影响.
- 为了确定表面特性与滴水去除的临界剪切速度之间的关系.
主要方法:
- 在五个微结构超表面,一个纳米结构碳纳米管表面和一个光滑的水表面上进行了实验.
- 滴滴体积 (5-50μL) 受到增加的空气速度,直到离开.
- 高速成像追踪滴滴尺寸和接触角度;测量出发时的空气速度.
主要成果:
- 滴滴出发速度强烈依赖于表面固体分数,随着固体分数的减少而减少.
- 接触角歇斯底里斯在起飞前增加,并作为滴水流动性的指标.
- 一个计算的阻力系数离开滴滴随着雷诺兹数的增加而下降.
结论:
- 结构化的超水表面可以显著减少滴滴离开所需的剪切流量.
- 较低的表面固体分数增强滴滴的流动性,使它们更容易被剪流移除.
- 接触角歇斯底里和表面固体分数是预测超水表面滴滴行为的关键参数.
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