在对称的纹理表面上通过自发的对称性破坏来推动Leidenfrost的推进
Songlin Shi1,2, Chen Ma1,2, Steffen Hardt3
1Department of Engineering Mechanics, AML, Tsinghua University, 100084 Beijing, China.
Science advances
|April 25, 2025
概括
对称的纹理可以通过蒸汽层的自发对称性破坏来推进液滴,展示了自我推进和潜在能量转换的新机制.
科学领域:
- 物理 物理学 物理
- 流体动力学 流体动力学
- 表面科学是一门学科.
背景情况:
- 莱登弗罗斯特效应描述了在热表面和液体之间形成的气体薄膜,使滴滴可移动.
- 之前的研究表明,表面纹理不对称对于自动推进来说至关重要.
- 在这种现象中动态对称性破坏的作用仍然未被探索.
研究的目的:
- 为了研究自发的对称性断裂在气液流的自动推进.
- 为了证明在对称的纹理表面上滴滴的自推力.
- 探索热力机械能量转换的潜力.
主要方法:
- 使用了水力动力学合驱动振荡器的模型.
- 使用计算流体动力学 (CFD) 模拟.
- 分析了滴量大小,温度和基质参数的影响.
主要成果:
- 在气液流中证明了自发的对称性破坏,产生了自我推进力.
- 显示的水滴是由对称表面上的蒸汽压力场驱动的.
- 在各种液体中观察到自我推进,包括液和乙醇.
结论:
- 气液界面的动态对称性破坏是液体大规模运动的关键.
- 对称的纹理表面可以诱导自我推进,挑战先前的假设.
- 这种机制为高效的热力机械能量转换提供了一个新的途径.
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