交叉扩散控制了一个振荡不稳定的三元混合物与索雷特效应的振荡不稳定
Berin Seta1, Ane Errarte2, Aliaksandr Mialdun3
1Department Civil and Mechanical Engineering, Technical University of Denmark, Denmark.
Physical chemistry chemical physics : PCCP
|June 2, 2023
概括
研究了三元混合物中的复杂流体动力学与索雷特效应. 振荡不稳定性源于相反的索雷特和热扩散系数,导致波浪模式和依赖交叉扩散.
科学领域:
- 流体动力学 流体动力学
- 化学物理 化学物理
- 非平衡的热力学 热力学
背景情况:
- 由于合的扩散和对流,三元混合物表现出复杂的动态.
- 索雷特效应是一种热扩散现象,在热梯度下显著影响混合物的行为.
- 了解这些动态对于涉及多组件系统的应用至关重要.
研究的目的:
- 通过实验和数值研究托卢-甲醇-环素混合物中的动态调节.
- 分析索雷特效应和交叉扩散在模式形成和不稳定中的作用.
- 阐明导致热重力柱振荡不稳定的条件.
主要方法:
- 使用热重力柱设置的实验研究.
- 三维混合动力学三维数值模拟.
- 分析索雷特系数,热扩散,交叉扩散和对流.
主要成果:
- 观察到主要的长波不稳定,表现为静止波.
- 确定了作为一个摇摆模式出现的二次不稳定性.
- 证明振荡不稳定性取决于交叉扩散系数 (D12) 的特定范围.
结论:
- 索雷特和二烯的热扩散系数对立的标志引发了振荡不稳定性.
- 交叉扩散在振荡模式的出现和稳定性中起着至关重要的作用.
- 不稳定性过渡到静止模式 (图灵式或单调) 在关键D12范围之外.
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