滴滴动力学在接触线上的作用 取决于剪切气体流量
Mehdi Mortazavi1,2, Sung Yong Jung3
1Department of Mechanical and Materials Engineering, Worcester Polytechnic Institute, 100 Institute Rd, Worcester, Massachusetts 01609, United States.
Langmuir : the ACS journal of surfaces and colloids
|July 21, 2023
概括
从气体流下的表面上垂落的滴滴受到惯性力的影响,而不仅仅是阻力. 滴体内的振荡运动会产生显著的惯性力,这有助于接触线的分离.
科学领域:
- 流体动力学 流体动力学
- 表面科学是一门学科.
- 微流体学 微流体学
背景情况:
- 由于表面张力和接触角歇斯底里,气滴在剪切气流下抵抗脱落.
- 当气体流使液滴变形超出其接触角歇斯底里极限时,就会发生脱落.
研究的目的:
- 为了研究在层状剪切气体流下增长滴的接触线分离过程.
- 分析滴滴动力学和惯性力在解机制中的作用.
主要方法:
- 使用高速成像,可视化在多孔层上生长的滴滴.
- 分析滴滴的局部速度和加速度,以应对不同的表面气体速度.
- 对惯力相对于粘附力和阻力力的量化.
主要成果:
- 观察到滴中的振荡运动,归因于阻力和表面张力之间的相互作用.
- 滴滴速度和加速度随着表面气体速度的增加而增加,从而导致更早的分离.
- 惯力有很大的贡献,达到粘附力的高达一半,与与对流性韦伯数相关的"山丘状"变化.
结论:
- 由滴滴振荡产生的惯性力与阻力力一起,在接触线的定义中起着至关重要的作用.
- 划分标准受阻力,惯力和滴滴粘附的联合作用的影响.
- 即使在低气体速度下,惯力相对于粘附力来说也是相当大的.
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