在剪切流中的疏水粗表面上产生泡生长
Jiang Li1, Xiaohe Li1, Chenyang Wang2
1School of Mechanical Engineering, University of Science and Technology Beijing, Beijing 100083, China.
Langmuir : the ACS journal of surfaces and colloids
|April 29, 2024
概括
气泡在流水中的疏水粗表面上生长,减少了阻力. 这发生在裂中由于剪切引起的压力下降而引起的异质核化,在中度剪切速率阻力降低中具有潜在的应用.
科学领域:
- 流体动力学 流体动力学
- 表面科学是一门科学.
- 材料科学是一种材料科学.
背景情况:
- 在疏水的粗表面上形成的气泡可以减少阻力.
- 在流量条件下,这些表面上泡生长的机制尚不清楚.
研究的目的:
- 在流量条件下的疏水粗表面上研究气泡的生长.
- 了解泡生长,表面特性和阻力减小之间的关系.
主要方法:
- 使用具有平行板设置的旋转转移计来创建旋转的流量场.
- 在不同的剪切速率下检查不同粗度和湿度的表面.
- 同时观察泡增长和测量阻力减小.
主要成果:
- 泡生长仅在疏水性粗表面上观察到.
- 检测到同时降低阻力,与气泡形成相关.
- 泡的生长归因于裂中的异质核形成,这是由剪流减少局部压力所驱动的.
- 开发了一个几何模型来描述基于接触角度和压力平衡的泡形状演变.
结论:
- 在流动下对疏水粗表面的泡生长是可行的,并导致阻力减少.
- 该过程依赖于裂中的异质核和局部压力变化,不需要极端条件.
- 这种现象在中等剪速环境中对阻力减轻有潜在的应用.
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