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Updated: Jun 4, 2025

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从弹道到扩散热传输的过渡在一个有断裂的链中
Anton M Krivtsov1, Vitaly A Kuzkin1, Vadim A Tsaplin1
1<a href="https://ror.org/02x91aj62">Peter the Great Saint Petersburg Polytechnic University</a>, Saint Petersburg 195251, Russia and <a href="https://ror.org/047pt5178">Institute for Problems in Mechanical Engineering RAS</a>, Saint Petersburg 199178, Russia.
Physical review. E
|December 18, 2024
概括
一维链中的键解离驱动了从弹性传热到扩散式传热的转变. 这项研究模拟了热传输,揭示了从富里埃的偏差.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 统计力学 统计力学
- 热力学是一种热力学.
背景情况:
- 在低维系统中的热传递可以表现出非扩散性行为.
- 了解从弹道运输到扩散运输的过渡对于纳米级热管理至关重要.
研究的目的:
- 在一维系统中研究从弹性转换到扩散热传递的转换机制.
- 开发和分析热传输的动力模型,以分离键链.
主要方法:
- 建模一个具有和粒子间力和键解离的单维链.
- 开发了一个动力模型,使用一种来自随机屏障反射的非相互作用准粒子气体.
- 准粒子气体的动力方程的分析解.
主要成果:
- 动力模型分析地证明了从弹性 (短时间) 到扩散性 (长时间) 热传输的过渡.
- 在扩散极限中,热传播表现为平方根对称,但偏离高斯形状,违反富里埃定律.
- 该模型显示与链动态的数值模拟具有良好的定性一致性.
结论:
- 键解离是一种关键机制,可以使热传输从弹性转变为扩散热传输.
- 拟议的动力模型为研究异常热传输提供了有价值的框架.
- 由于底层的微观动力学,在扩散模式中观察到与富里埃定律的偏差.
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