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在粘弹性流体的融合流中,elasto-惯性不稳定性
Mahmud Kamal Raihan1, Nayoung Kim1, Yongxin Song2
1Department of Mechanical Engineering, Clemson University, Clemson, SC 29634-0921, USA. xcxuan@clemson.edu.
Soft matter
|July 22, 2024
概括
这项研究揭示了粘弹性流体在T连接处融合的新流动模式. 弹性不稳定性以复杂的方式出现,与聚合物度有关,而不仅仅是流体弹性.
科学领域:
- 流体动力学 流体动力学
- 类风病学 类风病学 类风病学
- 聚合物科学 聚合物科学
背景情况:
- 在工程和自然现象中,T连接液体的融合至关重要.
- 之前的研究主要集中在牛顿流体上,使粘弹性过渡研究不足.
研究的目的:
- 系统地研究聚乙烯氧化物 (PEO) 溶液的融合流.
- 识别和描述中间流动模式和过渡状态.
- 探索弹性不稳定性和流体特性之间的关系.
主要方法:
- 对具有不同聚合物度和分子量的PEO溶液进行实验研究.
- 在增加雷诺兹数时观察流动模式.
- 对弹性不稳定性开始的分析.
主要成果:
- 两种新的流动发展路径与不断增加的雷诺兹数相结合.
- 一个"并置状态"的特征,具有明显的弹性和惯性带.
- 发现弹性不稳定值依赖于相对于其重叠值的聚合物度的强度定律.
结论:
- 在T结流中过渡到弹性不稳定性是复杂的,并且在很大程度上取决于聚合物度.
- 观察到的依赖性与诸如麦金利-帕克德尔标准等理论预测一致.
- 这项研究扩大了对弹性流体在合并流中的行为理解.
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