在悬浮液体下漂浮
Benjamin Apffel1, Filip Novkoski1, Antonin Eddi2
1ESPCI Paris, PSL University, CNRS, Institut Langevin, Paris, France.
Nature
|September 4, 2020
概括
垂直震动可以稳定大型液体层, 这种方法还可以产生反向浮力,使物体在液体上颠倒浮.
科学领域:
- 流体动力学
- 非线性动力学
- 表面物理
背景情况:
- 液体层通常由于重力诱导的雷利-泰勒不稳定性而崩,当它们放置在不太密集的介质上时.
- 垂直震动是一种通过动态平均有效重力的稳定液体的方法.
研究的目的:
- 通过对支空气层的共振激发来研究大型液体层的稳定.
- 探索物体在浮动液体层上颠倒浮动的现象.
- 理论预测和实验验证稳定反向浮动的条件.
主要方法:
- 使用对空气层的共振激发来支持大液体体积 (最多0.5L,宽20厘米) 的实验设置.
- 理论建模,以根据其质量预测稳定倒置浮体所需的最小激发.
- 实验观察和验证重体的选择性下降.
主要成果:
- 通过激发支层的空气层成功地升起了大型液体层.
- 在下方液体界面上建立稳定的反向浮力位置.
- 证实垂直震动可以逆转下面接口上的物体的有效引力.
- 保持反转浮动器所需的最小激发的验证理论预测.
结论:
- 垂直震动,通过共振激发,使大量液体能够悬浮.
- 这种技术创造了反直觉的稳定配置,
- 这些发现挑战了对界面现象和浮力的传统理解.
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