由于部分可混合的粘性指纹的流速,手指宽度的模式转换和非单调的变化
Ryuta X Suzuki1,2,3, Takahiko Ban4, Manoranjan Mishra5
1Tokyo University of Agriculture and Technology, Department of Chemical Engineering, Nakacho 2-24-16, Koganei, Tokyo 184-8588, Japan.
Physical review. E
|September 16, 2025
概括
部分混合系统中的粘性指纹 (VF) 显示出独特的模式. 增加流速会抑制滴滴的形成,改变手指的宽度,揭示了这些系统特有的非单调关系.
科学领域:
- 流体动力学 流体动力学
- 接口现象 接口现象
- 复杂的流体 复杂的流体
背景情况:
- 粘性指纹 (VF) 描述了当粘性较低的液体在多孔介质或Hele-Shaw细胞中取代粘性较高的液体时形成的类似手指的图案.
- 传统的VF研究将动力学分为完全混合和不混合的系统.
- 部分可混合系统代表了第三个,较少探索的类别,具有独特的界面行为.
研究的目的:
- 实验性地研究流速对部分可混合系统中粘性指纹模式的影响.
- 在不同的流量条件下,从滴滴模式转变为手指主导模式的特征.
- 阐明控制这些现象的基本机制及其对流速和流体性质的依赖.
主要方法:
- 实验性调查粘性指纹在部分可混合系统在一系列的流速.
- 对手指宽度和滴滴行为进行定量测量.
- 测量低粘度溶液的面积和测量自发滴滴运动的速度.
- 数字模拟用于验证实验观测和探索参数空间.
主要成果:
- 在中间流速下,滴滴形成被抑制,导致比不混合的VF更宽的粘性指纹.
- 在高流速下,手指的宽度接近不混合的VF.
- 确定了手指宽度和流量率 (毛细血管数) 之间的非单调关系,这对于部分混合系统来说是独特的.
- 数字模拟成功地重现了实验结果,包括滴滴抑制和手指扩大.
结论:
- 流速在部分可混合系统中显著影响粘性指纹形态.
- 观察到的非单调的指宽与流速的依赖性是部分可混合性的标志.
- 这项研究阐明了相位分离,滴滴动态和指纹模式之间的相互作用.
- 这些发现提供了对部分混合系统中复杂的流体移位现象的更深入的理解.
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