剪切驱动干扰中的缓慢和快速粒子:关键行为
1Department of Physics, Umeå University, 901 87 Umeå, Sweden.
Physical review. E
|September 19, 2023
概括
这项研究揭示了剪切驱动的干扰涉及不同的缓慢和快速粒子过程,影响剪切粘度. 缓慢的过程,与速度分布峰值相关,有助于粘度校正,脱离这种不寻常的关键现象中的相关性.
科学领域:
- 软物质物理学 软物质物理学
- 计算物理 计算物理
- 类风病学 类风病学 类风病学
背景情况:
- 剪切驱动的干扰是密集的颗粒材料和合体中观察到的关键现象.
- 了解粒子动力学与宏观质性质之间的关系至关重要.
- 之前的研究表明,剪切粘度在阻塞密度附近有分歧,但潜在的机制仍在争论中.
研究的目的:
- 分析2D剪切驱动干扰模型中粒子的速度分布.
- 为了研究粒子速度分布和剪切粘度组件之间的关系.
- 描述剪切驱动干扰的性质作为一个关键现象.
主要方法:
- 对2D剪切驱动干扰模型进行了广泛的模拟.
- 分析不同密度 (φ) 和低剪变速率 (γ̇) 的粒子速度分布.
- 将模拟结果与剪切粘度 (η) 的理论缩放分析进行比较.
主要成果:
- 粒子速度分布包括两个不同的组成部分:缓慢的过程和快速的过程.
- 剪切粘度分歧由两个术语组成,与快速和缓慢的过程直接相关,分别.
- 缓慢过程对剪切粘度的贡献可以从速度分布的峰值特征中预测.
结论:
- 剪切驱动的干扰表现出不寻常的关键行为,其中相关性和剪切粘度脱.
- 缓慢的过程,由较慢的粒子主导,控制了剪切粘度的校正到缩放项.
- 集体粒子运动主要由缓慢的过程控制,挑战传统的关键现象范式.
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