超临界甲的运输特性
Sergey A Khrapak1, Ferdinando Formisano2, Livia E Bove3
1Joint Institute for High Temperatures, Russian Academy of Sciences, 125412 Moscow, Russia.
Physical review. E
|August 19, 2025
概括
本研究将超临界甲扩散的实验数据与理论模型进行比较. 它确定了类似气体到类似液体行为的明显过渡,这对于理解运输特性至关重要.
科学领域:
- 热力学是一种热力学.
- 流体动力学 流体动力学
- 物理化学 物理化学
背景情况:
- 超临界流体在气相和液相之间表现出独特的特性.
- 了解分子扩散是预测超临界甲中运输现象的关键.
- 之前的研究报告了关于超临界甲分子扩散在广泛压力范围内的实验数据.
研究的目的:
- 将超临界甲中的实验分子扩散数据与莱纳德-斯模型的理论预测进行比较.
- 用斯托克斯-爱因斯坦-萨瑟兰关系来分析从气态转变为液态的动态行为.
- 要区分运输特性和刚性-流体状态的明显转换.
主要方法:
- 实验结果与基于列纳德-斯模型的理论预期进行比较.
- 在Chapman-Enskog近似中应用动态方法,用于低压,低密度的系统.
- 对于更高的压力和密度,利用冷密度缩放方法.
- 分析斯托克斯-爱因斯坦-萨瑟兰关系的链接自我扩散和剪切粘度.
主要成果:
- 动力方法在低压,低密度的极限上是充足的.
- 结密度缩放方法有效地描述了高压和高密度的行为.
- 动态交叉位于实验观察到的过渡到类似液体的分子扩散附近.
- 确定了两个截然不同的过渡:运输属性对称的交叉点和刚性-流体状态的开始.
结论:
- 这项研究为了解和预测超临界甲的运输特性提供了一个框架.
- 区分不同的过渡类型澄清了动态交叉和Frenkel线的相互矛盾的定义.
- 这些发现为超临界流体应用提供了实用的见解,在这些应用中,实验数据很少.
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