表面活性剂对泡形成在近静态状态下的超水表面的影响
Hangjian Ling1, John Ready1, Daniel O'Coin1
1Department of Mechanical Engineering, University of Massachusetts Dartmouth, Dartmouth, MA 02747, USA.
Biomimetics (Basel, Switzerland)
|June 25, 2025
概括
将表面活性剂添加到水中可以显著改变超水表面 (SHS) 上的泡形成. 气泡体积和基半径随着表面活性剂度的增加而减少,这是由于表面张力和接触角度的减少.
科学领域:
- 流体动力学 流体动力学
- 表面科学是一门学科.
- 合体化学 合体化学
背景情况:
- 在各种工业过程中,超疏水表面 (SHS) 上的气泡形成至关重要.
- 了解表面活性剂对这些现象的影响对于过程优化至关重要.
- 之前的研究已经探索了泡动态,但对SHS的综合影响需要进一步调查.
研究的目的:
- 实验性地研究表面活性剂度对超水表面泡形成动态的影响.
- 为了量化气泡脱离体积和基半径的变化,在变化的表面张力和接触角度下.
- 阐明在不同的表面活性剂条件下控制气泡形成的缩放规律.
主要方法:
- 在近静态状态下以恒定的流速在超疏水表面上通过一个孔口注入气体.
- 在水中的1-pentanol表面活性剂度的系统变化 (0至0.08mol/L).
- 测量表面张力,静态接触角度,气泡脱离体积和最大气泡底半径.
主要成果:
- 表面活性剂度增加导致泡脱落体积 (Vd) 和最大泡底半径 (Rdmax) 的减少.
- 在低度下,Vd和Rdmax与表面张力 (σ) 缩放为Rdmax~σ^1/2和Vd~σ^3/2.2.
- 在高度下,降低静态接触角度 (θ0) 和表面张力有助于降低Vd和Rdmax. 气泡形状表现出自我相似性,随着毛细血管的长度变大.
- 表面活性剂对气泡缩动态的影响最小,主要是减少时间和长度尺度.
结论:
- 表面活性剂的添加通过改变表面张力和接触角度,显著影响SHS上的泡形成.
- 该研究建立了气泡脱离体积和半径的缩放规律,取决于表面张力.
- 这些发现提高了对复杂的液体表面系统中泡形成的理解,这与微流体学和材料科学有关.
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