接口作为二维Cahn-Hilliard-Navier-Stokes流中的运输障碍
Nadia Bihari Padhan1,2, Rahul Pandit1
1Department of Physics, Indian Institute of Science, Bangalore 560012, India.
概括
二元流体流中的接口作为标记粒子的重要运输障碍. 这些屏障有效地捕获液滴中的颗粒,在较大的液滴半径中观察到更长的捕获时间.
科学领域:
- 流体动力学 流体动力学
- 流研究 流研究
- 接口现象 接口现象
背景情况:
- 二元流体流涉及复杂的接口动态.
- 了解跨这些接口的运输对于各种应用程序至关重要.
- 拉格朗的痕迹粒子提供了一种研究粒子分散的方法.
研究的目的:
- 调查接口作为2D二元流体流中的运输障碍物的作用.
- 量化界面对标记粒子的捕获效应.
- 探索影响在流体界面内的痕迹粒子保留的因素.
主要方法:
- 使用Cahn-Hilliard-Navier-Stokes (CHNS) 系统进行模拟.
- 采用二维CHNS方程的伪光谱直接数值模拟.
- 追踪拉格朗的痕迹粒子在一个相的滴中释放出来.
主要成果:
- 发现接口可以作为有效的运输障碍,长时间保留追踪器.
- 一滴水中的粒子分数呈指数级衰变,衰变时间与R0^3/2.3成比例.
- 与简单的循环外运输相比,追踪器的平均首次传输时间显著更长.
结论:
- 双流体流中的接口作为粒子传输的实质性障碍物.
- 滴滴大小和接口动态 (例如,Okubo-Weiss参数,周边波动) 影响追踪器的捕获.
- 这些发现提供了关于乱的两相流中的接口运输机制的见解.
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