在散装聚合物流中最大分散减小
Yi-Bao Zhang1,2, Feng Wang1, Sheng-Hong Peng1
1Northwestern Polytechnical University, Institute of Extreme Mechanics, School of Aeronautics, National Key Laboratory of Aircraft Configuration Design, Key Laboratory for Extreme Mechanics of Aircraft of Ministry of Industry and Information Technology, Xi'an 710072, China.
Physical review letters
|October 25, 2025
概括
流体中的聚合物添加剂产生两种模式:减散减散和最大减散减散 (MDR). 具有板状的MDR模式,发生在聚合物效应达到积分长度尺度时.
科学领域:
- 流体动力学 流体动力学
- 聚合物物理 聚合物物理
- 流研究 流研究
背景情况:
- 聚合物流涉及流体流和聚合物添加剂之间的复杂相互作用.
- 了解能量消散和结构对于描述这些流动至关重要.
研究的目的:
- 在散装聚合物流中实验性地研究流动模式和结构.
- 确定导致最大消散减少 (MDR) 的条件,并描述相关的流量结构.
主要方法:
- 使用了高分辨率的三维速度测量.
- 分析重点是聚合物度对能量消散和动态的影响.
主要成果:
- 确定了两种不同的聚合物对能量消耗的影响模式:减少消耗和MDR.
- 发现,当受聚合物影响的尺度达到积分长度尺度,而不是Lumley尺度时,MDR制度就会发生.
- 在MDR制度中,板状和应变结构占主导地位,稳定了剪切层.
结论:
- MDR 模式代表了在散装聚合物流中普遍的流动状态.
- 结果提供了聚合物流的相位图和对粘弹性流体流动模式的见解.
- 在MDR中,板状状结构很重要,有助于预测流动行为.
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