Transition from wall modes to multimodality in liquid gallium magnetoconvection
Transition from wall modes to multimodality in liquid gallium magnetoconvection
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DOI：
10.1103/physrevfluids.8.103503
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发表时间：
2023-10
影响因子：
2.7
通讯作者：
Yufan Xu;S. Horn;J. Aurnou
中科院分区：
文献类型：
--
作者：
Yufan Xu;S. Horn;J. Aurnou
本文介绍了垂直磁场作用下液态镓中瑞利-巴姆纳德对流的室内-数值耦合实验。实验在两个径高比为2.0的圆柱形容器中进行，在不同的热强迫（瑞利数）和磁场强度（钱德拉塞卡数）下进行。实验室测量和数值模拟证实，我们有限圆柱形储罐中的磁对流是通过非漂移附壁模式开始的，这与半无限域的渐近预测很好地吻合。随着超临界的增加，实验和数值热测量以及数值速度数据揭示了不同方位模态的壁面模态之间的转变以及壁面为主的对流到壁面和内部多模态之间的转变。这些转变也反映在传热数据中，结合以往的研究，将大参数空间内液态金属磁对流的开始与超临界湍流行为联系起来。对液态金属中磁对流和旋转对流的总传热行为进行了比较和讨论。
Coupled laboratory-numerical experiments of Rayleigh-Bénard convection in liquid gallium subject to a vertical magnetic field are presented. The experiments are carried out in two cylindrical containers with diameter-to-height aspect ratioand 2.0 at varying thermal forcing (Rayleigh numbers) and magnetic field strength (Chandrasekhar numbers). Laboratory measurements and numerical simulations confirm that magnetoconvection in our finite cylindrical tanks onsets via nondrifting wall-attached modes, in good agreement with asymptotic predictions for a semi-infinite domain. With increasing supercriticality, the experimental and numerical thermal measurements and the numerical velocity data reveal transitions between wall mode states with different azimuthal mode numbers and between wall-dominated convection to wall and interior multimodality. These transitions are also reflected in the heat transfer data, which combined with previous studies connect onset to supercritical turbulent behaviors in liquid metal magnetoconvection over a large parameter space. The gross heat transfer behaviors between magnetoconvection and rotating convection in liquid metals are compared and discussed.