An experimental and computational investigation was carried out in an eiectromagneticaily stirred Woods metal system, and the associated free-surface deformation was studied. The free-surface velocities were measuredat various strengths of the applied magnetic fields using high-speed video photography. The effect of the magnetic field strength of the electromagnetic stirrer on the free surface deformation was studied by varying the position of the melt relative to the electromagnetic stirrer. Thecalculated free surface deformation was comparedto experimental observations made on a laboratory-scale installation.

A mathematical representation has been developed to represent the electromagnetic force field used to impart rotary motion to a cylindrically shaped molten metal pool. Problems of this type arise in the electromagnetic stirring of continuous casting systems. The formulation given here introduces two new facets which have been neglected by previous investigations, namely, an allowance for the nonlinear dependence of the magnetic flux intensity on the radial distance, and the coupling between the melt velocity and the induced field. It is shown that neglecting these factors may involve errors in the 20%–50% range.

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A model is developed to calculate the flow field produced by electromagnetic stirring generated by a rotating magnetic field. This study has considerable importance due to its applicability to continuous casting systems. Three cases are considered, the first, in which steady continuous stirring is studied, and the numerical results are found to agree well with the experimental observations by other workers. In the second case, alternating stirring is examined, and the critical role of switching frequencies is discussed. Finally, a preliminary allowance is made for free surface deformation for the continuous stirring situation. The effective viscosity is deduced from the transport equations for K, the turbulence kinetic energy, and for ∊, the rate of viscous dissipation. The transport equation for K is modified to account for turbulence enhancement due to electromagnetic effects.