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The 3-D magnetic field numerical analysis of a full-scale magnetic shielding room is advantageously performed by using the equivalent B--H method. In the proposed numerical method, the magnetic anisotropy and the nonlinearity due to material magnetic saturation are taken into account, by directly introducing the magnetization characteristics of the considered materials. An equivalent element, which substitutes the plural finite elements having different material properties for a homogeneous one, is introduced to reduce the number of unknowns. When the equivalent B--H method is applied to a full-scale magnetic shielding room (length 5.8 m, width 3.3 m, height 3.3 m), the measured leakage magnetic flux density distribution is found to be in good agreement with the calculated one, proving the reliability of the proposed approach, which can be adopted in many large-scale electromagnetic field problems. [ABSTRACT FROM AUTHOR]

Abstract. 30 magnetohydrodynamic calculation model taking into consideration of heat transfer and solidification as well as free surface is developed in order to evaluate the characteristics of molten metal using electromagnetic stirring (EMS). A shadow method that calculates electromagnetic force in consideration of free surface transition is proposed to reduce computing time and keep sufficient accuracy. A calculated free surface of Mercury under 200 Hz magnetic field shows an adequate agreement with experimental one. Calculation results applied to continuous casting process taking into consideration of heat transfer and solidification are in good agreement with operation data. This model introduces that EMS makes the solidified shell uniform and dynamic deviation of temperature stable. [ABSTRACT FROM AUTHOR]

Presents information on a study which examined a three-dimensional magneto-hydrodynamic method for evaluating the free surface motion of molten metal. Calculation method; Calculation results; Conclusions.

Presents information on a study which developed a three-dimensional magnetohydrodynamic calculation model for evaluating the characteristics of molten metal using electromagnetic stirring. Equation of heat transfer and solidification; Effect of the electromagnetic stirring; Calculation results; Conclusions.

We evaluate an effect of the dual in-mold electromagnetic stirring (M-EMS) which is arranged in series to control the molten steel velocity distribution using magnetohydrodynamic Calculation. A stirring force ratio (SFR) defined as Fu/F1 where Fu is an electromagnetic force of upper M-EMS and F1 is the one of the lower M-EMS is introduced as an index of input. The value of SFR at the optimal condition that meniscus velocity is almost zero, but some velocity is realized at lower M-EMS position. Especially, the SFR condition to have no velocity at free surface is extremely rigorous. This means that it is very difficult to be stable at meniscus by the dual M-EMS system. The lower velocity hardly changes when the SFR changes. [ABSTRACT FROM AUTHOR]

In this paper, we develop and examine permanent magnet synchronous motors (PMSMs) by use of both stator and rotor cores made of nanocrystalline magnetic materials (NMMs). We report core loss properties of the PMSM with the NMM under inverter excitation. In addition, we compare core losses of the PMSM with conventional non-oriented (NO) steel sheets under inverter excitation to discuss the core loss characteristics of the NMM motor. In average, under inverter excitation, the reduction ratio in core loss of the PMSM made of NMM is about 60% as compared with the core loss of the PMSM with NO sheets. In particular, the average decrease obtained by using NMM rotor core instead of NO rotor core is about 30%. [ABSTRACT FROM AUTHOR]

The authors investigate the effects of double-axis electromagnetic stirring (DAEMS) in continuous casting process, which is composed of a rotational electromagnetic stirrer and a vertical electromagnetic stirrer, using unsteady 3-D hydrodynamic calculation of the molten gallium model. To evaluate the free-surface stability, averaged standard deviation of the free surface is calculated. From the calculation results, it is found that there is an optimum intensity balance between a vertical magnetic stirrer and a rotational magnetic in order to stabilize the free surface. [ABSTRACT FROM AUTHOR]

We propose a new type of magnetic shield structure, in which some closed magnetic paths surround a defined space. Because there are some openings between paths, the freedom in designing and the ease of constructing a shield room are attained. This structure shows better magnetic shield performance than conventional shield structures when openings between magnetic paths, widths of magnetic paths, and weight distribution of magnetic materials are designed appropriately. [ABSTRACT FROM AUTHOR]