超冷水滴冲击超疏水表面的反弹模式,控制温度和湿度
Chunfang Guo1,2, Lei Liu1, Rui Yang1
1College of Mechanical Engineering, Donghua University, Shanghai 201620, China.
Langmuir : the ACS journal of surfaces and colloids
|July 12, 2023
概括
超疏水表面可以通过使水滴反弹而防止冰的形成. 然而,冰显著阻碍了这种抗结冰效应,导致水滴粘附,即使在有纹理的表面.
科学领域:
- 材料科学 材料科学 材料科学
- 表面科学是一门学科.
- 流体动力学 流体动力学
背景情况:
- 超水表面通过反水性提供被动的抗结冰潜力.
- 饼反弹机制理论上是为了最大限度地减少滴水表面接触时间,防止结冰.
- 超疏水表面对超冷却滴的抗结冰性能仍未得到充分研究.
研究的目的:
- 在受控的温度和湿度下,研究滴滴对超水表面的冲击动态.
- 检查表面质地,温度,韦伯数和对滴滴接触时间和反弹行为的影响.
- 确定超疏水表面的抗结冰性能限制.
主要方法:
- 一个后阵列超表面 (PSHS) 和一个平面超表面 (FSHS) 的制造.
- 系统地调查滴滴撞击动态,包括接触时间和弹跳行为.
- 控制实验改变了表面温度,韦伯数和表面结条件.
主要成果:
- 平面超表面 (FSHS) 呈现出常规反弹和完全粘附,粘附与卡西-温泽尔过渡有关.
- 后阵列超表面 (PSHS) 显示了四种模式:饼反弹,常规反弹,部分反弹和完全粘附.
- 饼反弹,以短暂的接触时间为特征,增强抗结冰作用,但在较低的温度或时失败.
- 冰积累扰乱了饼的反弹,减少了储存的毛细血管能量,导致滴滴粘附.
结论:
- 在PSHS上的饼反弹模式通过最小化接触时间提供了优越的抗结冰作用.
- 表面的冰严重损害了饼的反弹机制,导致粘附.
- 滴滴核化和湿过渡,加剧了低温和,决定了抗结冰性能限制.
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