Wave Mode Coupling and Instability in the Internal Wave in Aluminum Reduction Cells

  • Nobuo Urata


In aluminum reduction cells, the interfacial surface wave causes uneven anode-cathode distance over the electrolytic zone and reduces the efficiency of electrolysis. In the past, the coupled partial differential equations, describing the electromagnetic perturbation in the cell, were formulated and solved with various mathematical methods. In this article, a Fourier expansion method is used for understanding the interaction of the various non-perturbed gravity waves. A proper mathematical treatment of the boundary condition, a critical factor for solving the equations, is presented. The result is summarized as the mode interactions, governed by the symmetry of the vertical magnetic field and the symmetry of the wave modes. The dominant mechanism of the instability is explained and the various practical methods for magnetic field compensation are reviewed.


aluminum reduction instability wave MHD 


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© The Minerals, Metals & Materials Society 2016

Authors and Affiliations

  • Nobuo Urata
    • 1
  1. 1.SunnyvaleUSA

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