在双分散密集悬浮中剪切加厚期间的秩序-混乱过渡
Xueqiong Fu1, Yanwei Liu2, Jibao Lu3
1School of Civil Engineering and Architecture, Anyang Normal University, Anyang 455000, China; Shenzhen Institute of Advanced Electronic Materials, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518103, China.
Journal of colloid and interface science
|February 22, 2024
概括
悬浮中的剪切厚度通过顺序-混乱过渡来澄清. 最佳粒子大小分布 (PSD) 揭示了层结构如何变化,影响粘度和流体流量.
科学领域:
- 类风病学 类风病学 类风病学
- 材料科学 材料科学 材料科学
- 计算物理 计算物理
背景情况:
- 由于微观的摩擦接触,多式悬浮中的剪切加厚是复杂的.
- 了解风病学需要分析粒子大小分布 (PSD).
研究的目的:
- 阐明剪切加厚过程中顺序-乱序过渡的基本机制.
- 研究颗粒大小分布对悬浮体质学的影响.
主要方法:
- 使用了离散粒子模拟.
- 模拟涵盖了广泛的剪切速率和低于临界体积分数 (φc) 的PSD.
主要成果:
- 一个秩序-混乱过渡被确定为剪切加厚的关键机制.
- 最优的PSD (ζ1=0.26) 显示了粒子按层次结构排序,然后这些结构失序,导致粘度跳跃.
- 具有稳定的分层结构的双分散悬浮 (ζ1=0.50) 在剪切加厚过程中保持流动性.
结论:
- 顺序-混乱过渡对于在粒子碰撞主导的惯性流中剪切加厚至关重要.
- 微观结构变化显著影响宏观的质性质.
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