揭示了在结构化表面上增强流程沸传热的基本原理
Mohammad Jalal Inanlu1, Vishwanath Ganesan1, Nithin Vinod Upot1
1Department of Mechanical Science and Engineering, University of Illinois, Urbana, IL 61801, USA.
Science advances
|November 8, 2024
概括
这项研究使用现场玻璃镜检查,揭示流水沸过程中的微观泡动力学. 该技术解释了微/纳米结构表面如何增强热传递,在上高达391%.
科学领域:
- 表面科学和微流体学
- 热力学和传热热力学
背景情况:
- 微型和纳米结构的表面可以改善双相传热.
- 目前的诊断方法不足以理解增强机制,阻碍了合理的表面设计.
研究的目的:
- 引入并应用现场玻璃镜,用于在流水沸过程中研究微观泡动力学.
- 阐明微型/纳米结构表面热传递增强的机制.
- 为了将表面孔径分布与热性能联系起来.
主要方法:
- 现场玻璃镜用于实时观察泡动态.
- 在化学蚀刻的和铜管中进行和流沸实验.
- 孔测量用于孔径分布分析.
主要成果:
- 镜检查揭示了显著的微观泡行为,影响热传输.
- 尽管表面结构相似,但在 (高达391%) 和铜 (高达41%) 之间,热传递系数的增强差异很大.
- 毛孔尺寸分布与观察到的热性能相关.
结论:
- 在现场玻璃镜是一种强大的工具,用于了解流水沸热传递机制.
- 表面微观结构和孔隙特征极大地影响热传递增强.
- 开发的技术可以推进对两相现象的研究.
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