分子热传输通过一个时间周期的温度梯度
Renai Chen1, Tammie Gibson2, Galen T Craven2
1Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
The Journal of chemical physics
|May 20, 2024
概括
分子网中的振荡温度梯度使得可控的热传输和能量储存成为可能. 这项研究揭示了不同振荡参数如何影响这些新出现的热特性.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 热力学是一种热力学.
- 计算材料科学科学 计算材料科学
背景情况:
- 温度梯度的周期调节显著改变了热传输.
- 静态温度梯度不表现出像修改热导率或时间延迟能量存储这样的现象.
研究的目的:
- 为了研究振荡温度梯度对分子格子模型中的热传输特性的影响.
- 探索由温度振荡引起的新出现的能量储存,释放和热导电机制.
主要方法:
- 使用了分析分析和分子动力学模拟.
- 一个随机能量框架和一个修改的不平衡格林的函数方法被用来导出热电流表达式.
- 该研究的重点是分子格子系统,其中有两个热浴体验振荡温度差异.
主要成果:
- 温度振荡诱导新兴的能量储存,能量释放和热导电机制.
- 这些机制可以通过调整振荡梯度的频率,波形和振幅来精确控制.
- 该研究成功地获得了非静止平均能量流下的热流表达式.
结论:
- 振荡温度梯度为控制分子格子中的热传输提供了一种新的方法.
- 开发的理论框架为理解在时间依赖的热梯度下振动热传递提供了一种通用方法.
- 这项研究为设计具有可调节热性能的材料为先进应用开辟了道路.
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