不同质的溶剂散射与颗粒重新排列相结合,在剪切稀释非布罗恩悬浮中产生异质的溶剂散射
Tomoharu Terayama1, Akira Furukawa1
1Institute of Industrial Science, University of Tokyo, Meguro-ku, Tokyo 153-8505, Japan. terayama@iis.u-tokyo.ac.jp.
Soft matter
|July 18, 2024
概括
这项研究揭示了颗粒运动和溶剂流在密集悬浮中如何相互作用,解释了剪切稀释. 水力动力学力显著影响颗粒的行为和悬浮特性.
科学领域:
- 类风病学 类风病学 类风病学
- 流体动力学 流体动力学
- 计算物理 计算物理
背景情况:
- 密集的非布罗恩悬浮物表现出剪切稀释,这是一个尚未完全理解的现象.
- 粒子动力学和溶剂水力学之间的相互作用至关重要但复杂.
研究的目的:
- 在剪切稀释非布罗恩悬浮中数量研究粒子运动和溶剂水力学的合动力学.
- 为了阐明在密集悬浮中剪切稀释背后的机制.
主要方法:
- 数字模拟,包括用于水力动力学相互作用的光滑配置方法.
- 排除摩擦接触力以建模低剪速条件.
主要成果:
- 证明了与空间相关的粘性消散和粒子运动,其特征长度取决于剪切速率.
- 观察到显著的粒子密度变化,表明合作间隙和流通道形成/破坏.
- 确定了水力动力相互作用作为限制粒子重排的关键因素.
结论:
- 水力动力相互作用在限制颗粒在密集悬浮中的重新排列方面发挥着重要作用.
- 这些相互作用显著影响悬浮剂的宏观质性质.
- 这些发现提供了对复杂流体中剪切稀释的更深入的理解.
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