在平行板间隙分离期间的脱离力,由简单的收益应力流体介导.
Vítor Hugo de Oliveira Pereira1, Wilson Barros2
1Departamento de Física, Universidade Federal de Pernambuco (UFPE), Cidade Universitária, 50670-901, Recife, Pernambuco, Brazil.
The European physical journal. E, Soft matter
|January 23, 2024
概括
这项研究揭示了收益应力流体在引下如何表现,在小间隙显示不稳定性,在较大的间隙显示稳定流动. 我们分离了粘度,毛细体和产应力对引力的贡献.
科学领域:
- 流体力学的流体力学
- 类风病学 类风病学 类风病学
- 软物质物理学 软物质物理学
背景情况:
- 收益应力流体表现出复杂的流动行为.
- 了解引力对于工业应用至关重要.
研究的目的:
- 监测和分析收益应力流体的正常引力反应.
- 为了研究限制几何和初始差距对流体行为的影响.
- 为了区分和量化粘度,毛细度和屈服应力对引力的贡献.
主要方法:
- 实验设置涉及两个以恒定速度分离的圆形平行板.
- 视觉检查萨夫曼-泰勒不稳定性和指纹模式.
- 应用赫歇尔 - 布克利模型来分析引力缩放.
主要成果:
- 萨夫曼-泰勒不稳定性观察到狭窄的初始间隙,以指纹模式为特征.
- 稳定的圆对称性在较大的初始间隙中保持,表明不稳定性不存在.
- 连锁的引力贡献允许分离粘度,毛细体和产量应力效应.
结论:
- 该研究成功地隔离和量化了在产应力流体中的个体力贡献.
- 不稳定性是影响流体行为和小规模引力的关键因素.
- 赫舍尔-布克利模型有效地描述了不同系统的引力扩展.
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