粘性气泡如何崩:曲率驱动的水力动力学中的拓和折对称不稳定性
Benny Davidovitch1, Avraham Klein2
1Physics Department, University of Massachusetts, Amherst, Amherst, MA 01003.
概括
液体泡压力的突然变化会导致非线性表面动态,导致独特的流动模式和辐射纹. 这项研究揭示了粘性流体在快速压缩下表现的新物理.
科学领域:
- 流体动力学 流体动力学
- 非线性表面动力学 不线性表面动力学
- 粘性液体的行为
背景情况:
- 弹性变形和非惯性粘性流之间的既定二元性在液膜平衡的快速变化下被打破.
- 在双曲曲的液体薄膜中的几何非线性表面动力学,特别是在突然减压时,仍然在很大程度上未被探索.
研究的目的:
- 为了研究液体薄膜被迫脱离机械平衡的尚未探索的非惯性但几何非线性表面动力学.
- 确定这些动态背后的驱动机制,重点关注表面曲率的时间变化.
- 分析浮动泡快速压缩的具体情况.
主要方法:
- 一个浮动泡的理论分析正在经历快速压缩.
- 研究拓不稳定性和前部传播在不断变化的泡表面.
- 检查单一的流结构,类似于弹性系统中的偏离.
- 对称性破坏的不稳定性导致放射性纹形成的分析.
主要成果:
- 表面曲率的时间变化驱动粘性液体薄膜中的非线性动态.
- 一个具有单一流结构的平面区域发生了自发的核形成和扩张.
- 圆圈压缩会触发破坏对称性的不稳定性,从而在平整的泡表面上产生辐射纹.
- 观察到的动态被描述为"凝"物理学的非平衡分支,曲率变化速率与电荷相似.
结论:
- 这项研究揭示了粘性膜中由曲率变化驱动的新型表面动态,与传统的弹性-粘性类比不同.
- 辐射纹的形成是由圆环压缩引发的对称性破坏不稳定性解释的.
- 突出了线性稳定性分析预测与纹波长实验观测之间的差异,这表明需要先进的理论框架.
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