Numerical modelling of axisymmetric electromagnetically driven flows in thin layers

Abstract

We present the results of the numerical modelling of deceptively simple steady axisymmetric electromagnetically driven flows in thin disk-like layers of a weakly conducting electrolyte. The fluid motion is caused by an azimuthally acting Lorentz force appearing when a radial current flows in the electrolyte layer placed on top of a magnet with a vertical polarisation. The small layer thickness and the circumferential direction of the driving force suggest that the flow in such a system should be essentially uni-directional. However, it was found that not only is the flow fully three-dimensional, but multiple solutions can exist for the same set of governing parameters. References

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