在Weeks-Chandler-Andersen流体中运输系数的结密度缩放
1Joint Institute for High Temperatures, Russian Academy of Sciences, 125412 Moscow, Russia.
The Journal of chemical physics
|April 1, 2024
概括
维克斯-钱德勒-安德森 (WCA) 流体的运输系数显示结密度缩放 (FDS). 这种缩放行为在各种简单的流体中是相似的,这表明密集的流体与的相互作用有一个普遍的原则.
科学领域:
- 物理 物理学 物理
- 物理化学 物理化学
- 热力学是一种热力学.
背景情况:
- 了解简单的古典流体的行为在热力学中至关重要.
- 传输系数,如自我扩散,剪切粘度和导热率是流体的关键性质.
- 维克斯-钱德勒-安德森 (WCA) 模型是研究流体性质的共同理论框架.
研究的目的:
- 为了研究维克斯-钱德勒-安德森 (WCA) 流体的运输系数.
- 为了确定WCA流体是否表现出结密度缩放 (FDS).
- 将WCA流体的FDS与其他流体模型和真实物质进行比较.
主要方法:
- 分析WCA流体沿着等热体的传输系数 (自我扩散,剪切粘度,热导率).
- 观察到的缩放行为的比较与已建立的模型,如伦纳德-斯和硬球体流体.
- 探索相关概念,如斯托克斯-爱因斯坦关系和气体-液体动态交叉.
主要成果:
- WCA流体的运输系数在等热线上表现出结密度缩放 (FDS).
- 在WCA流体中FDS的功能形式与在Lennard-Jones流体,硬球体流体和液化贵气中观察到的功能形式密切相关.
- 这表明FDS代表了简单的古典流体与的相互作用的准普遍相应状态原理.
结论:
- 这项研究证实了基于结密度缩放的密集简单古典流体的准普遍相应状态原理.
- 这些发现表明,FDS是具有的排斥相互作用的流体的强大特征.
- 为密集的WCA流体的传输系数提出了简单的配合公式,有助于未来的研究和应用.
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