对于周期层系统的离散热方程,允许界面热阻:一般配方和分散分析
1Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry, Russian Academy of Sciences, Chernogolovka, Moscow Region 132432, Russia and Samara State Technical University, ul. Molodogvardeiskaya 244, Samara 443100, Russia.
Physical review. E
|June 22, 2024
概括
这项研究为多层系统推导了离散热方程,揭示了有限的热干扰速度和独特的高频行为. 离散方法是研究超快热传导在元材料的最好选择.
科学领域:
- 物理 物理学 物理
- 材料科学 材料科学 材料科学
- 热力学是一种热力学.
背景情况:
- 多层周期系统中的热传导对于元材料应用至关重要.
- 现有的连续模型在描述超快热传输现象时存在局限性.
研究的目的:
- 导出和分析多层周期系统的离散热方程.
- 研究热干扰的行为,并开发热传输性质的分析表达式.
主要方法:
- 考虑层间热阻的离散热方程的推导.
- 在 ω-k 空间中分析分散关系.
- 获得衰减距离,相位和群速的分析表达式.
主要成果:
- 离散方程意味着有限的热干扰速度和正的解决方案.
- 与连续模型相比,速度的分析表达式显示了不寻常的高频行为.
- 离散方程具有固有的频率和波数限制,与连续模型不同.
结论:
- 离散方法是研究超短时间尺度上的超快速热传导的首选方法.
- 这项工作为分析周期性多层元材料的波形热传导提供了一个工具.
- 导出方程为工程材料热传输的基本物理提供了洞察力.
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