在横槽几何学中对纯弹性流动不对称性的风湿学影响
Arisa Yokokoji1, Stylianos Varchanis1, Amy Q Shen1
1Okinawa Institute of Science and Technology Graduate Univerisity, Onna-son, Okinawa 904-0495, Japan. simon.haward@oist.jp.
Soft matter
|December 6, 2023
概括
粘弹性流体中的弹性和剪切薄化显著影响横槽几何体中的流动不对称性. 了解这种相互作用是预测弹性不稳定的关键.
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:
- 交叉槽几何学中的粘弹性流可以从对称状态过渡到不对称状态.
- 这种过渡通常归因于在临界流速 (韦森堡数,Wi) 时的弹性效应.
- 剪切稀释在这种转变中的作用仍然是一个研究领域.
研究的目的:
- 为了研究流体弹性和剪切稀释对交叉槽几何中的流动不对称性的联合影响.
- 确定这些特性之间的相互作用如何影响不对称流动的出现和发展.
- 根据弹性和剪切稀释参数绘制流量状态的地图.
主要方法:
- 实验研究使用具有不同类型的质性质的聚合物溶液.
- 流速测量以测量流动不对称性 (I) 作为Wi和剪切稀释参数 (S) 的函数.
- 使用线性简化的Phan-Thien-Tanner模型进行数值模拟.
主要成果:
- 流动不对称性随着Wi超出临界值而增加,但也取决于剪切稀释 (S) 的程度.
- 对于一些解决方案,当剪切稀释最小时 (低S),在较高的Wi值时恢复流程对称性.
- 在Wi-S空间中的流状态图说明了流 asimmetry 和流体 rheology 之间的关系.
结论:
- 流体弹性和剪切稀释,以及它们的相互作用,都是控制跨槽流动中的弹性不稳定性的关键因素.
- 这些发现凸显了考虑纯弹性之外的学复杂性的重要性.
- 结果为理解和预测这种几何体中的流动行为提供了一个框架.
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