在低雷诺兹数的棒状聚合物的稀释溶液中的定向顺序和拓缺陷
L Puggioni1,2, S Musacchio1
1Dipartimento di Fisica and INFN, <a href="https://ror.org/048tbm396">Università degli Studi di Torino</a>, via P. Giuria 1, 10125 Turin, Italy.
Physical review. E
|August 20, 2024
概括
刚性棒状聚合物与流量保持一致,以减少摩擦,而混乱的流量则来自旋转障碍和拓缺陷. 这种行为类似于稀释聚合物溶液中的活体阴性流.
科学领域:
- 流体动力学 流体动力学
- 聚合物物理 聚合物物理
- 计算物理学的计算物理.
背景情况:
- 刚性棒状聚合物的稀释溶液表现出复杂的流动行为.
- 了解聚合物方位动态对于预测溶液性质至关重要.
- 低雷诺兹数流可以显示非直观的现象.
研究的目的:
- 为了研究聚合物导向和混乱流动之间的关系.
- 阐明驱动聚合物溶液中"流式"行为的机制.
- 在二维和三维空间维度中分析这些动态.
主要方法:
- 使用了直接的数值模拟 (DNS).
- 这项研究的重点是刚性棒状聚合物的稀释溶液.
- 保持了低雷诺兹数条件. 保持了低雷诺兹数条件.
主要成果:
- 棒状聚合物与速度场对齐,以最大限度地减少溶剂摩擦.
- 旋转障碍和混乱的流动与强烈的旋转梯度相关.
- 在导演字段中拓缺陷的出现和相互作用驱动"乱式"行为.
结论:
- 聚合物定向显著影响混乱的流动动力学.
- 观察到的"类似流"的行为类似于活跃的阴性流.
- 直接的数值模拟为复杂的聚合物流体相互作用提供了宝贵的见解.
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