A method to study the physical phenomena of the molten metal under the AC magnetic field has been required to design the electromagnetic (EM) dam system. This confines a side of the molten metal by Lorentz force without contact between the side wall and the molten metal. In this work, we have developed a numerical analysis method to predict the 3-D phenomena of the molten metal considering the free surface. To evaluate steady the state of the molten metal including the free surface, the integrated computational errors are eliminated after certain iteration step. This process avoids the solution diverged and provides the converged steady state solution. However, although the error elimination process neglects the physical phenomena of smaller scale than the elimination time step related, this method could predict slowly varying the surface shape obtained by the experiment. By using this method, the effects of magnetic field direction and the EM boundary condition on the surface shape are investigated. The profile of Lorentz force corresponding to the direction of magnetic field and boundary condition was found to affect the flow pattern resulting in the change of the steady state surface shape.

A high frequency electromagnetic field (HFEMF) that is applied to the surface of a molten metal is able to generate a Lorentz force on the surface of the molten metal. This force can be used to seal the molten metal leakage without contact, which makes the quality of metal products purer and the seal system used perform longer. To make this technique possible, it is required to analyze the surface shape and the surface instability when HFEMF is applied to the molten metal surface. It is known from experiment with various kinds of molten metal that the fluctuation of the surface occurs under the applied HFEMF. This fluctuation becomes stronger as the HFEMF is increased. The fluctuation is strongly connected to the instability criteria of the surface. This research has been carried out to make it clear how the HFEMF causes the surface fluctuation of the molten metal, and how it determines the surface shape and stability region. Also, the effects of gradient of HFEMF and DC magnetic field have been investigated.

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A two-dimensional simulation code of a discharge-pumped excimer laser was developed to study the effect of spatial discharge non-uniformity on laser output performance.The code consists of a circuit equation, a continuity equation to calculate two-dimensional electric field, a steady-state Boltzmann equation, and rate equations.The preionization distribution was found to affect the electron and the excited particle distributions and hence the laser beam profile. Even with uniform-field electrodes, the calculated electric field distribution was not uniform, being effected by the configuration of surrounding structures, and varying in time with the changing discharge plasma conditions. The electric field surrounding insulating structures were found to increase prior to gas breakdown and to decrease afterwards.