在具有导电度梯度的剪切稀释流体中,电动流动不稳定性
To-Lin Chen1,2, Mahmud Kamal Raihan2, Seyed Mojtaba Tabarhoseini2
1Department of Engineering Science, National Cheng Kung University, Tainan 70101, Taiwan. loudyfu@mail.ncku.edu.tw.
Soft matter
|January 8, 2025
概括
在微通道电动力流中由香丹 (XG) 诱导的流体剪切稀释,降低了电场不稳定的电场值. 然而,波的特性,如速度和振幅,随着聚合物度的增加而下降.
科学领域:
- 流体动力学 流体动力学
- 电动运动学 电动运动学
- 微流体学 微流体学
背景情况:
- 电动动力学不稳定性 (EKI) 以电场下的微通道中的流体接口的波浪形式表现.
- 之前的研究主要集中在牛顿流体上,忽视了生物和化学样本中常见的非牛顿行为.
研究的目的:
- 实验研究流体剪切稀释对电动力学不稳定性 (EKI) 的影响.
- 分析香糖 (XG) 度对EKI波特征和发病值的影响.
主要方法:
- 在牛顿缓冲溶液中添加丹 (XG),以诱导剪切稀释特性.
- 在微通道中实验观察和测量EKI波的开始,传播速度,振幅和频率.
- 考虑流体性质变化的临界电力雷利数的分析.
主要成果:
- 与牛顿解决方案相比,在XG解决方案中,EKI开始的电场值显著降低.
- 波传播速度,振幅和频率在XG的存在下降.
- 增加XG度降低了值电场和临界电Rayleigh数,表明剪切稀释增强了EKI.
结论:
- 液体剪切稀释,用香丹实现,有效降低电场值的电动动力学不稳定性.
- 虽然剪切稀释增强了EKI的发作,但波特征表现出高聚合物度的非单调趋势,与仅基于电宇宙速度的预测分歧.
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