Abstract The understanding of fluid wakes is of fundamental importance in several technological applications. In this paper, we present an experimental and numerical study of vortex wakes produced by a traveling localized Lorentz force in a thin layer of electrolyte contained in a narrow channel. The experimental set up consists of an open rectangular container with two parallel electrodes placed along its longest walls and connected to a power source that supplies a uniform DC current to the fluid layer. A permanent magnet located underneath the container is moved with a constant velocity so that the interplay of the moving magnetic field and the applied transversal current generates a traveling Lorentz force that stirs the electrolyte and creates different vortex wakes according to the flow conditions. Attention is focused on the effect of lateral walls on the flow patterns, therefore, two containers of different width and magnets of different sizes were used to vary the blockage parameter. Numerical simulations using a quasi-two-dimensional model agree qualitatively with experimental visualizations. Further, flow transition maps built from experimental and numerical results are presented.

中文翻译：

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狭窄通道中电磁产生的涡街

摘要 流体尾流的理解在若干技术应用中具有根本重要性。在本文中，我们展示了由行进的局部洛伦兹力在包含在狭窄通道中的电解质薄层中产生的涡流尾迹的实验和数值研究。实验装置由一个开放的矩形容器组成，两个平行电极沿其最长的壁放置，并连接到为流体层提供均匀直流电流的电源。位于容器下方的永磁体以恒定速度移动，以便移动磁场和施加的横向电流的相互作用产生行进的洛伦兹力，该力搅动电解质并根据流动条件产生不同的涡流尾流。注意力集中在侧壁对流动模式的影响上，因此，使用两个不同宽度的容器和不同尺寸的磁铁来改变阻塞参数。使用准二维模型的数值模拟与实验可视化定性一致。此外，还介绍了根据实验和数值结果构建的流动过渡图。