在提升流中使用流体环形的指纹稳定和粘附力
Írio M Coutinho1, Pedro H A Anjos2, Rafael M Oliveira2
1Departamento de Física, Universidade Federal de Pernambuco, CCEN, Recife, Pernambuco 50670-901, Brazil.
Physical review. E
|February 17, 2024
概括
引入流体环层稳定粘性指纹不稳定性,提升Hele-Shaw流. 这种方法可以控制界面干扰,而不会显著改变粘合力,提供了一个新的控制策略.
科学领域:
- 流体动力学 流体动力学
- 接口现象 接口现象
- 控制不稳定的控制不稳定性
背景情况:
- 提升Hele-Shaw细胞流动包括在板块之间拉伸粘性液滴.
- 粘性指纹不稳定性,一种萨夫曼-泰勒不稳定性,发生在空气-油界面,很难控制.
- 控制界面干扰对于技术和工业应用至关重要.
研究的目的:
- 提出和分析一种替代方法来控制升起的Hele-Shaw流中的界面干扰.
- 为了研究中间流体环在中心油滴上的稳定作用.
- 为了确定流体环对粘附力的影响.
主要方法:
- 分析了一种经过修改的Hele-Shaw电池配置,具有三流体,两接口,双连接系统.
- 用第二阶段的扰动模式合方法来研究形态和稳定性行为.
- 在稳定和不稳定的接口条件下计算了附着力.
主要成果:
- 中间流体环显著稳定了中心油滴的接口.
- 稳定效率取决于环的粘度和厚度.
- 粘附力在很大程度上保持不变,与薄的流体外,无论接口的稳定性.
结论:
- 一个中间流体环是稳定粘性指纹的有效策略,用于提升Hele-Shaw流.
- 流体环提供了一种可控制的方法来管理界面干扰.
- 在环的边界上有指纹的存在对粘附力的影响是可以忽略不计的.
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