在微重力条件下,湿液体泡的粗转变
Marina Pasquet1, Nicolo Galvani2,3, Alice Requier1
1Université Paris-Saclay, CNRS, Laboratoire de Physique des Solides, 91405, Orsay, France. dominique.langevin@universite-paris-saclay.fr.
Soft matter
|August 8, 2023
概括
国际空间站 (ISS) 泡研究揭示了泡生长规律如何过渡. 研究人员观察到一个关键的液体部分,泡不再接触,不同于随机紧密包装由于粘合力较弱.
科学领域:
- 物理 物理学 物理
- 材料科学 材料科学 材料科学
- 流体动力学 流体动力学
背景情况:
- 泡粗受重力驱动排水的影响.
- 了解泡生长规律对于预测泡稳定性至关重要.
- 之前的研究集中在干燥 (φ → 0) 和稀释 (φ → 1) 极限.
研究的目的:
- 在微重力下研究泡粗,以抑制排水.
- 确定泡生长规律之间的过渡.
- 分析临界液体分数 (φ*) 和它与随机密封 (φrcp) 的关系.
主要方法:
- 在国际空间站 (ISS) 上进行了泡粗化实验.
- 控制的液体分数 (φ) 在15%至50%之间.
- 测量了粗化速率和确定了临界液分数 (φ*).
- 独立确定的随机密封包装体积分数 (φrcp).
- 进行了互补的地面实验来研究泡相互作用.
主要成果:
- 最干燥的泡和泡液体的粗化速度与理论预测一致.
- 在临界值φ*时,观察到泡生长规律之间的急剧交叉.
- 发现 φ* 比 φrcp大得多.
- 邻近的气泡并非所有都在超过 φ* 的范围内接触.
结论:
- 微重力泡研究提供了无引力效应的泡动力学的见解.
- 临界液体分数 (φ*) 标志着泡接触和生长规律的过渡.
- 软粘性泡相互作用可能解释了为什么φ*超过φrcp.
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