交叉和主要扩散系数对非反应性扩散系统中对称性破坏的影响
Berin Šeta1, Jon Spangenberg, Mounir M Bou-Ali2
1Technical University of Denmark, Department of Civil and Mechanical Engineering, Koppels Allé, Kgs. Lyngby 2800, Denmark.
Physical review. E
|October 21, 2025
概括
在无需化学反应的情况下,在扩散触发的对流中可能发生对称性破坏,由成分依赖的扩散驱动. 这一发现揭示了流体动力学和楼梯不稳定的新模式.
科学领域:
- 流体动力学 流体动力学
- 化学工程是化学工程的组成部分.
- 地质物理学 地质物理学
背景情况:
- 扩散触发的对流在稳定的流体系统中发生.
- 不稳定性可以导致双扩散 (DD) 或扩散层对流 (DLC) 模式.
- 非对称的图案传统上归因于化学反应.
研究的目的:
- 为了研究扩散触发对流的模式形成.
- 探索构成依赖的扩散和交叉扩散的作用.
- 了解叠加混合物中对称性的破坏.
主要方法:
- 流体混合物的理论建模.
- 扩散系数的分析.
- 模拟对流模式.
主要成果:
- 对称性破裂只能由于构成依赖的扩散而发生.
- 交叉扩散被认为是模式不对称的一个关键因素.
- 解释了一系列共存的模式和楼梯不稳定现象.
结论:
- 在这个系统中,化学反应对于对称性破坏并不必不可少.
- 构成依赖的扩散和交叉扩散为流体不稳定性提供了新的见解.
- 这项研究促进了对分层流体模式形成的理解.
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