相关实验视频
Updated: Jun 29, 2025

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Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
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在高度分层的平面Couette流中不稳定,适用于超临界流体
B Bugeat1, P C Boldini1, A M Hasan1
1Process and Energy Department, Delft University of Technology, Leeghwaterstraat 39, 2628 CB Delft, The Netherlands.
概括
强密度和粘度分层导致平面Couette流动的不稳定. 最小的动力粘度触发了这一点,由特征尺度控制,无论分层类型如何.
科学领域:
- 流体动力学 流体动力学
- 不稳定理论 不稳定理论
背景情况:
- 平面库埃特流是流体动力学的基础.
- 密度和粘度的分层显著影响了流动稳定性.
- 了解不稳定机制对于预测流体行为至关重要.
研究的目的:
- 为了研究平面库埃特流与强密度和粘度分层的稳定性.
- 为了确定控制流动不稳定的关键参数.
- 阐明在分层流中观察到的不稳定性背后的物理机制.
主要方法:
- 分析稳定性模型的推导使用长波近似和零碎线性基流.
- 数字稳定性计算以验证模型并分析干扰旋转的产生.
- 应用广义的Fjørtoft标准来识别不稳定条件.
主要成果:
- 证明存在一个一般化的拐点,满足一般化的Fjørtoft的标准,当一个最小的动力粘度是存在的.
- 确定了粘度最小的特征尺度作为主要不稳定性控制参数.
- 解释不稳定性是由于两个旋转波的相互作用而产生的,这种不稳定性是由分层流中的剪切和惯性巴洛克林效应所驱动的.
结论:
- 运动粘度的最小值,特别是在超临界流体中的维多姆线附近,是不稳定的主要原因.
- 该研究为稳定性图提供了定量预测,并确定了主要的不稳定性机制.
- 这些发现提供了对各种流体和流量的不稳定性的见解,包括可混合的流体.
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