在具有可移动/透内部壁的非平衡系统中自发过程的方向.
Robert Hołyst1, Paweł J Żuk1, Anna Maciołek1,2
1Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warszawa, Poland.
Entropy (Basel, Switzerland)
|August 29, 2024
概括
热力学第二定律控制非平衡系统,包括热流中的气体. 这项研究将热力学原理扩展到在非平衡条件下预测各种气体系统的墙壁运动.
科学领域:
- 热力学是一种热力学.
- 统计力学 统计力学
- 流体动力学 流体动力学
背景情况:
- 经典热力学和第二定律对于平衡系统已经得到了很好的确立.
- 非平衡热力学需要扩展来描述动态过程.
- 了解热流和粒子相互作用对于复杂系统至关重要.
研究的目的:
- 研究热力学不等式在非平衡热流场景中的适用性.
- 在非平衡条件下的各种气体系统中分析墙壁运动的方向.
- 将这些发现综合到一个非平衡热力学第二定律的通用框架中.
主要方法:
- 在理想气体,范德瓦尔斯气体和二进制混合物中分析热流.
- 在隔离系统中引入可移动的内墙.
- 应用热力学不等式 (dU-đQ≤0和dE-đQ-đWs≤0) 来预测运动.
- 包括引力场和透墙来得出阿基米德的原理.
- 考虑理想气体的Couette (剪切) 流量.
主要成果:
- 不等式dU-đQ≤0决定了理想气体和范德瓦尔斯气体,以及二元混合物的热流中的墙壁运动方向.
- 这种不平等仍然适用于引力场和透的墙壁,导致阿基米德的热流原理.
- 对于库埃特流,不等式dE-đQ-đWs≤0控制了墙壁运动.
- 为非平衡热力学第二定律建立了一个统一的框架.
结论:
- 热力学第二定律可以扩展到涉及热流的非平衡系统.
- 热力学不等式为预测各种非平衡条件下的系统行为提供了一种一致的方法.
- 这项研究将多种不同的非平衡现象统一在一个单一的理论结构中.
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