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在超冷液体中,剪切诱导的扩散性
Mangesh Bhendale1, Jayant K Singh1, Alessio Zaccone2
1Department of Chemical Engineering, Indian Institute of Technology, Kanpur, Uttar Pradesh 208016, India.
The Journal of chemical physics
|October 8, 2025
概括
在剪切超冷液体中,分子扩散率与剪切速率线性增加,不同于对简单液体的预测. 本研究使用修改后的斯莫鲁霍夫斯基方程来解释这种现象,并与模拟和实验保持一致.
科学领域:
- 非平衡物理学的物理学.
- 凝聚物质物理学 凝聚物质物理学
- 化学物理 化学物理
背景情况:
- 泰勒-阿里斯理论预测了简单的剪切液体中扩散性对二次剪切速率的依赖.
- 超冷的液体表现出对比的线性剪切速率对扩散率的依赖,这是非平衡系统中的一个关键观察.
研究的目的:
- 在剪流下的超冷液体中获得有效分子扩散率的理论公式.
- 为了解释在超冷液体中观察到的线性扩散性增强.
主要方法:
- 基于斯莫鲁霍夫斯基扩散-对流方程的公式的导出.
- 纳入一个代表拥挤的能源景观的能源屏障模型.
- 理论预测与分子模拟和实验数据的比较.
主要成果:
- 衍生式预测了有效的扩散率,在剪切速率中,校正术语是线性的.
- 理论预测与各种液体的数值模拟有合理的一致性.
- 发现扩散度的增强与温度成反比例,与零剪切粘度成正比.
结论:
- 该研究提供了一个理论框架,解释了超冷液体中线性剪切诱导的扩散性增强.
- 这些发现使理论预测与非平衡液体的实验和模拟结果相协调.
- 衍生式为超冷液体在剪切应力下的行为提供了洞察力.
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