表面形态对滴滴扩散和反弹动态的影响在次冷却的超水表面上
Matic Može1, Yuheng Shang2, Samo Jereb3
1Faculty of Mechanical Engineering, University of Ljubljana, Aškerčeva c. 6, SI-1000, Ljubljana, Slovenia. matic.moze@fs.uni-lj.si.
Scientific reports
|August 12, 2025
概括
超疏水表面有效地排斥水,但浅的微观结构通过减少液体接触来增强在低温下排斥力. 表面特征显著影响滴滴反弹和粘附动态.
科学领域:
- 表面科学与工程 表面科学与工程
- 流体动力学 流体动力学
- 材料科学 材料科学 材料科学
背景情况:
- 低冷的超疏水表面对于航空航天,能源和制冷至关重要.
- 微尺度的表面形态影响排水性和恐冰性.
- 了解这些表面上的滴水冲击动态是优化性能的关键.
研究的目的:
- 为了研究表面微观结构 (深度,类型) 如何影响超水表面的滴滴行为 (扩散,反弹,结).
- 分析温度和速度对滴水表面相互作用的影响.
- 为了确定微观结构在低温液滴撞击动态中的作用.
主要方法:
- 激光制造的超疏水表面的制备,其深度 (3-30微米) 和特征 (随机,定向微通道) 不同.
- 在韦伯数 (50-185) 和表面温度 (25°C至-30°C) 进行的滴滴撞击测试.
- 高速成像用于分析扩散,反弹和粘附现象.
主要成果:
- 表面形态对最大传播的影响最小;温度降低减少了9.5%的传播.
- 最差的反弹性能发生在We ≈ 120,过渡到喷,导致粘附.
- 接触时间随着温度的下降显著增加,观察到部分粘附时间超过20毫秒.
结论:
- 微结构深度和固体-液体接触分数显著影响滴滴反弹和附着在次冷却表面.
- 由于接触分数较低,浅特征的表面在次冷温度下表现出优异的排水能力.
- 在较高湿度下形成会增加能量消散和滴滴固定,阻碍反弹,而不依赖表面形态.
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