墙壁滑动和剪切带之间的相互作用在一个厚性热的产量应力流体中
Michela Geri1, Brice Saint-Michel2, Thibaut Divoux2
1Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Soft matter
|July 10, 2024
概括
我们发现了新型的剪切-绑定行为在thixotropic流体,在哪里流动带流动带.
科学领域:
- 类风病学 类风病学 类风病学
- 软物质物理学 软物质物理学
- 流体动力学 流体动力学
背景情况:
- 锡克索托普的产量应力流体表现出复杂的流动行为.
- 非单调的流量曲线表明机械不稳定性.
- 标准的类风湿常常错过了独特的流动力学.
研究的目的:
- 调查克索托普性产量应力流体的局部动态.
- 在模型抛凝中特征剪切带.
- 开发一个模型来解释观察到的流体现象.
主要方法:
- 结合超声波速度测量与标准类风湿测量.
- 研究了一些模型的烯基凝.
- 提出了一个差异杆规则模型.
主要成果:
- 在下降的流量曲线分支中发现了一个原始的剪切结合场景.
- 流带速度是由应用的剪率设置的,而不是临界剪率.
- 观察到非微不足道的墙壁滑动取决于应用的剪切速率.
- 开发了一个捕捉流动带范围和墙壁滑动的模型.
结论:
- 拟议的模型解释了粘性流体中的剪接和墙面滑动.
- 墙壁滑动作为额外的自由度,放松了经典的剪切绑定约束.
- 在流动带尺寸接近粒子大小的低切割速率上出现合作效应.
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