球链和高度弹性纤维在粘性流体中在重力下沉的动力学
H J Shashank1, Yevgen Melikhov1, Maria L Ekiel-Jeżewska1
1Institute of Fundamental Technological Research, Polish Academy of Sciences, ul. Pawińskiego 5B, 02-106 Warsaw, Poland. mekiel@ippt.pan.pl.
Soft matter
|June 6, 2023
概括
这项研究揭示,在粘性液体中落的柔性球链很少在直线上移动,经常旋转并变形为U或W等复杂的形状.这些动态使用珠子弹模型准确地模拟.
科学领域:
- 流体动力学 流体动力学
- 软物质物理学 软物质物理学
- 类风病学 类风病学 类风病学
背景情况:
- 了解粘性液体中柔性结构的行为对于各种应用至关重要.
- 以前的研究往往简化了链动力学,忽视了平面外运动和复杂的变形.
研究的目的:
- 实验性地研究单双球链在高度粘性流体中的引力沉动力学.
- 描述这些链的非平面运动和形状演变.
- 用数值模拟来验证实验发现.
主要方法:
- 使用两个摄像头对球链运动的实验观测.
- 一个灵活的丝的数值模拟,模拟为一个珠弹链.
- 应用多极扩张的斯托克斯方程与滑校正 (HYDROMULTIPOLE代码).
主要成果:
- 单个球链表现出显著的外平面旋转和变形,形成U和W形状.
- 链条的动态高度依赖于链条的长度和初始配置.
- 数字模拟成功地重现了观察到的实验形状演变.
- 两个球链显示出基于初始距离的变化相对运动 (接近或分离).
结论:
- 粘性流体中的柔性球链在重力下显示复杂的非平面动态.
- 带有斯托克斯动态的珠弹模型提供了对这些现象的准确表示.
- 这项研究提供了关于在低雷诺兹数流中柔性细丝的行为的一些见解.
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