表面峰谷特征对在Leidenfrost温度下滴滴撞击动态的影响
Yunlong Jiao1, Jiaxiang Wang1, Yuhang Guo1
1Institute of Tribology, Hefei University of Technology, Hefei 230009, China.
Langmuir : the ACS journal of surfaces and colloids
|September 18, 2024
概括
微纹理表面提高了Leidenfrost的温度,但与微柱状表面相比,负斜率的微孔表面显示出优异的散热能力,为先进的冷却技术提供了潜力.
科学领域:
- 表面科学与工程 表面科学与工程
- 热传递和流体动力学 热传递和流体动力学
- 材料科学是一种材料科学.
背景情况:
- 莱登结现象对于各种应用中的热传递至关重要.
- 微纹理表面可以改变表面特性和传热特性.
- 了解纹理表面上的滴水冲击动态对于优化冷却至关重要.
研究的目的:
- 为了研究在Leidenfrost条件下影响微纹理表面的水滴的动态行为.
- 为了比较负倾斜 (micropit) 和正倾斜 (micropillar) 表面对Leidenfrost温度和散热的影响.
- 分析微纹面积占用率和韦伯数对滴滴冲击动态和冷却效率的影响.
主要方法:
- 利用高速摄影来捕捉滴滴撞击动态.
- 采用皮秒激光微加工,以创建独特的微孔和微柱状表面纹理.
- 研究的表面具有不同的微纹理占地面积和不同的韦伯数.
主要成果:
- 与光滑表面相比,微孔和微柱表面都会提高莱登冰的温度.
- 微孔表面显示Leidenfrost温度增加,占地面积更高,而微柱状表面显示相反的趋势.
- 负倾斜的微孔表面表现出优越的散热性能,特别是在50%的占用率下,由于优化了蒸汽流动力学.
结论:
- 表面的斜率显著影响滴水的行为和热量转移在Leidenfrost条件下.
- 负斜率的微孔表面提供了更高的冷却效率,表明它们具有高密度散热的潜力.
- 韦伯数影响滴滴冲击动态,影响反弹和断裂现象.
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