滴滴对层状超热粒子的影响的动态行为
Yunlong Jiao1, Xidong Hu1, Yongqing Zhu1
1Institute of Tribology, Hefei University of Technology, Hefei 230009, China.
Langmuir : the ACS journal of surfaces and colloids
|August 11, 2023
概括
这项研究将滴滴对超热粒子的影响分为六种模式,揭示了Leidenfrost点随着粒子大小的减少而减少. 了解这些动态对于工业应用至关重要.
科学领域:
- 流体动力学 流体动力学
- 热传递是一种热传递.
- 材料科学是一种材料科学.
背景情况:
- 滴滴对加热表面的影响涉及复杂的现象,如泡核和沸模式的变化.
- 了解这些相互作用对于诸如喷雾干燥和冷却等工业过程至关重要.
研究的目的:
- 为了研究和描述单滴对超热层粒子的冲击行为.
- 确定影响滴水蒸发模式的关键力量.
- 分析颗粒大小对莱登弗罗斯特点的影响.
主要方法:
- 在不同温度下对超热层状颗粒的滴滴撞击的实验观测.
- 分析包括惯性 (F_I),毛细血管 (F_C) 和蒸汽蒸发 (F_V) 的力量.
- 对粒子大小,温度和韦伯数 (We) 效应的研究.
主要成果:
- 确定了六种特征性滴水冲击模式:薄膜蒸发,泡泡沸,浸泡沸,喷雾沸,过渡沸和薄膜沸.
- 由于粒子间孔隙效应,随着粒子大小的增加,Leidenfrost点 (LFP) 降低.
- 滴滴直径的变化与高度的变化成反比例;最大扩散和反弹高度随粒子大小而变化,但速度保持独立.
结论:
- 滴滴对超热粒子的影响力学是由惯性,毛细血管和蒸汽力控制的.
- 颗粒大小显著影响莱登冰点和冲击形态.
- 这项研究增强了对液滴-粒子相互作用的理解,以提高工业安全和效率.
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