微观洞察Knudsen和电磁效应对封闭的半孔金属凝的导热性
Haiyan Yu1, Ning Guo1, Anqi Chen1
1Institute of Thermal Science and Technology, Shandong University, Jinan 250061, China.
Gels (Basel, Switzerland)
|September 26, 2025
概括
一个新的Voronoi模型准确地预测了中孔金属凝的导热性,考虑到像Knudsen效应这样的微观效应. 这项研究有助于设计用于高温应用的先进隔热材料.
科学领域:
- 材料科学 材料科学 材料科学
- 热力工程是热力工程中的一个.
- 纳米技术纳米技术
背景情况:
- 准确的热特征介质金属凝对于高温应用至关重要.
- 宏观模型往往忽略了影响热传递的微观效应.
- 了解这些影响是开发有效隔热的关键.
研究的目的:
- 引入一种新的预测方法,用于封闭的半孔金属凝中的导热.
- 将克努森效应和微观电磁相互作用纳入热模型.
- 为设计高性能隔热系统提供一个工具.
主要方法:
- 开发一个相当的沃罗诺伊模型.
- 包括Knudsen效应和微观电磁相互作用.
- 模型预测与实验导热数据的比较.
主要成果:
- 与实验结果相比,预测模型的平均误差为5.35%.
- 导热率随着孔隙性而降低,随着温度而增加.
- 在1μm孔径大小左右观察到的最低导热率为17.47W/m·K.
- 克努森主导的条件抑制了小孔尺寸的导电热传递.
- 电磁分析显示了增强辐射散射的等离子共振.
结论:
- 沃罗诺伊模型准确地预测了中孔金属凝中的导热率.
- 微尺度效应显著影响热传递,特别是在Knudsen主导的条件下.
- 这些发现支持用于高温应用的先进隔热设计.
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