在U槽微通道中与突然扩大的沉浸动态
Guan-Lin Chen1, Guan-Yu He1, Yu-Jane Sheng1
1Department of Chemical Engineering, National Taiwan University, Taipei 106, Taiwan.
Langmuir : the ACS journal of surfaces and colloids
|July 26, 2023
概括
这项研究探讨了突然扩大的U槽中的流体流动,根据接触角度和Concus-Finn细丝识别了四种流动类型. 流动行为取决于这些角度和槽尺寸.
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
- 计算物理 计算物理
背景情况:
- 研究浸泡动态对于理解微流体装置和多孔介质中的流体运输至关重要.
- 孔克斯-芬恩 (CF) 丝的存在大大复杂化了毛细血管驱动的流动,特别是在突然扩大的几何形状中.
- 之前的研究还没有完全描述接触角度,CF丝和U槽几何体内的流动行为之间的相互作用.
研究的目的:
- 为了研究与突然膨胀相连接的矩形U槽中的沉浸动态.
- 分析Concus-Finn (CF) 丝对流体流动模式的影响.
- 根据关键接触角度和几何参数,识别不同的流动模式.
主要方法:
- 采用多体消散粒子动力学 (DPD) 模拟来模拟流体行为.
- 在开放式和封闭式突然扩大配置中分析了浸泡动态.
- 多种接触角度 (θy),CF丝的临界角度 (θf),以及主要流量的临界角度 (θc) 来确定流量类型.
主要成果:
- 在开放式的突然放大中确定了四种不同的流体类型,由 θy, θf和 θc之间的关系决定.
- 观察到角流和主流的发生取决于这些关键角度,具体的模式导致缺席或存在.
- 证明扩大的U槽 (le) 的长度显著影响流动动力学,特别是在可以发生填充的闭端配置中.
结论:
- 接触角和CF线丝之间的相互作用控制了U道中的复杂的浸泡动态,并导致了突然的扩大.
- 几何因素,如扩大截面的长度,在确定最终流体分布方面发挥着关键作用.
- 这些发现提供了对毛细血管流动模式的详细理解,这对于设计微流体系统和预测有限几何体内的流体行为至关重要.
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