液体金属滴滴在较厚的水层上反弹更高.
Yuhang Dai1,2, Minfei Li1, Bingqiang Ji1
1Department of Mechanical Engineering, City University of Hong Kong, Hong Kong, 999077, China.
Nature communications
|June 14, 2023
概括
液体金属滴滴令人惊的是从水面上完全反弹,挑战粘附. 这种反弹随着水厚度的提高而改善的现象,为流体动力学和控制提供了新的见解.
科学领域:
- 流体动力学 流体动力学
- 材料科学是一种材料科学.
- 表面科学是一门科学.
背景情况:
- 由于其导电性和灵活性,液态金属 (LM) 对柔性电子,软机器人和芯片冷却至关重要.
- 在LM上有一层氧化物层通过对基板的粘附来阻碍运动.
- 了解LM滴滴行为对于高级应用程序至关重要.
研究的目的:
- 为了研究液体金属滴在水层上的异常反弹现象.
- 阐明观察到的微不足道的粘附和增加的恢复系数背后的机制.
- 探索在流体控制和滴滴动力学方面的潜在应用.
主要方法:
- 实验观察液体金属滴滴对不同厚度的水层的影响.
- 使用高速成像分析滴滴反弹的分析.
- 理论建模以解释滑膜和毛细血管压力的作用.
主要成果:
- 液体金属滴滴在水层上表现出完全反弹,附着度最小.
- 恢复系数随着水层厚度的增加而增加.
- 一种低粘度的水滑膜可以防止直接接触液滴和固体,减少能量消耗.
结论:
- 完全的反弹归因于被困的水滑膜和负毛细血管压力.
- 在液体金属滴子上自发散布的水会影响归还系数.
- 这些发现提高了对复杂的液滴动态的理解,并为流体控制提供了新的途径.
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