International Journal of Applied Electromagnetics and Mechanics - Volume 13, issue 1-4

Authors: Moses, A.J. | Konadu, S.N.

Article Type: Research Article

Abstract: A non-destructive system using a Hall effect I.C. sensor has been used to measure the distribution of the vertical component of stray magnetic field on the opposite surfaces of a magnetised specimen of high permeability, grain-oriented electrical steel. An optical microscope was used to establish positions of grain boundaries in order to explain differences in field profiles outside the systematic accuracy of measurements. It was found that unlike previously assumed, grain boundaries may not necessarily be …perpendicular to the sheet surface so different field distribution may occur. This should be considered when evaluating local power loss from surface sensor movements. Future studies are also necessary to quantify the effect of this phenomenon in the interpretation of surface or bulk properties of electrical steels using surface field sensors. Show more

DOI: 10.3233/JAE-2002-489

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 13, no. 1-4, pp. 339-342, 2002

Authors: Gavrichkov, V.A. | Kuz'min, E.V. | Ovchinnikov, S.G. | Mamalis, A.G.

Article Type: Research Article

Abstract: Generalized tight-binding method is developed to strongly correlated electron systems. Evolution of the band structure of CuO_2 layer with hole doping from the undoped charge transfer antiferromagnetic insulator to the optimally doped paramagnetic metal is obtained. Effective low energy Hamiltonian is given by a t-J-I model that allows to compare magnetic mechanism and symmetry of pairing in cuprates and ruthenates on equal footing.

DOI: 10.3233/JAE-2002-342

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 13, no. 1-4, pp. 343-348, 2002

Authors: Senda, Ikuo | Shoji, Teruaki | Araki, Masanori | ITER Japan Home Team, Group: | ITER Joint Central Team, Group:

Article Type: Research Article

Abstract: The system analyses of the magnetic field control system in the International Thermonuclear Experimental Reactor (ITER) are described. The analyses are performed by using a model of the closed loop system, which consists of the data analysis of diagnostics, the controller, the power supply of coils and the tokamak plant. The characteristics of the magnetic field control system in ITER are discussed and it is shown that the control system designed during the ITER engineering design …activities satisfies its requirements. The important roles of eddy currents in optimizing the magnetic field control system in ITER are also discussed. Show more

DOI: 10.3233/JAE-2002-345

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 13, no. 1-4, pp. 349-357, 2002

Authors: Yoon, H.K. | Lee, S.P. | Seok, C.S. | Kohyama, A.

Article Type: Research Article

Abstract: Low activation ferritic steels have been developed for a candidate of structural materials in nuclear fusion reactor applications. This paper dealt with the effects of rolling direction and side groove on the fracture toughness of low activation ferritic steel, JLF-1 Steel (9Cr-2W-V-Ta). The fracture toughness of JLF-1 steel showed the anisotropy in the rolling direction. In the case of J-R curve, J_{Q} and slope of the longitudinal JLF-1 steel (BML) for …the rolling direction were a slight larger than those of transverse JLF-1 Steel (BMT) at room temperature. In order to obtain the valid fracture toughness of JLF-1 Steel through the UC method, the CT specimen with a side groove of 40% was recommended. Show more

DOI: 10.3233/JAE-2002-491

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 13, no. 1-4, pp. 359-364, 2002

Authors: Takase, K. | Akimoto, H.

Article Type: Research Article

Abstract: An integrated ICE (Ingress-of-Coolant Event) test facility was constructed to demonstrate that the ITER (International Thermonuclear Experimental Reactor) safety design approach and design parameters for the ICE are adequate. Major objectives of the integrated ICE test facility are to estimate the performance of an integrated pressure suppression system and obtain the validation data for safety analysis codes and clarify the two-phase flow behavior under vacuum. The integrated ICE test facility simulates the ITER …components with a scaling factor of 1/1600. The modified TRAC-PF1 code is used to verify the integrated ICE experimental results. From the present study the effectiveness of the ITER pressure suppression system was verified experimentally and analytically, and then, it was clarified quantitatively that the prediction accuracy of the modified TRAC-PF1 code is very high. Show more

DOI: 10.3233/JAE-2002-490

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 13, no. 1-4, pp. 365-372, 2002

Authors: Smolentsev, S. | Abdou, M. | Kunugi, T. | Morley, N. | Satake, S. | Ying, A.

Article Type: Research Article

Abstract: Liquid wall concept has a significant place in the Advanced Power Extraction (APEX) study as a part of the US program on Nuclear Fusion. In the present paper, different approaches currently developed for modeling liquid wall magnetohydrodynamics and heat transfer in APEX have been presented. Turbulent flows of low-conductivity liquids, such as molten salts (Flibe), are analyzed using a two-equation turbulence model and Direct Numerical Simulation. The analysis of liquid metal flows under a strong reactor …magnetic field is based on the magnetohydrodynamic equations for laminar flows. Show more

DOI: 10.3233/JAE-2002-343

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 13, no. 1-4, pp. 373-379, 2002

Authors: Kitajima, Sumio | Nakanishi, Shigeyuki | Hashizume, Hidetoshi

Article Type: Research Article

Abstract: In this paper, we present experimental results of improvement for plasma confinement by controlling electric field with electron injection [1]. In order to generate the negative radial field, we inserted a hot cathode into the plasma and then biased negative voltage. We observed the plasma parameter changes after the hot cathode biasing: the increase of line density, the fluctuation suppression, the negative radial electric field formation, the plasma rotation, and the increase of the energy confinement …time. These results suggest that the improvement of plasma confinement by the formation of negative radial electric field is achieved. Show more

DOI: 10.3233/JAE-2002-344

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 13, no. 1-4, pp. 381-385, 2002

Authors: Jänicke, Lutz | Kost, Arnulf

Article Type: Research Article

Abstract: One of the major advantages of adaptive mesh generation is the optimum fitting of the mesh to the problem, leading to good memory efficiency. By suitably choosing the refinement parameters, the adaptive mesh generation is also time efficient. As the best refinement parameters depend on the problem to be solved and can also change during the adaptive solution process, they must be chosen dynamically. The choice is based on the error distribution, that is available from …the local error estimation. Therefore no additional computational cost arises due to the dynamic parameter setting. Show more

DOI: 10.3233/JAE-2002-361

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 13, no. 1-4, pp. 387-392, 2002

Authors: Jordan, Andrzej

Article Type: Research Article

Abstract: This paper presents a general concept of electromagnetic field parallel computations using super-computers and cluster system of workstations. In principle, all numerical algorithms of electromagnetic field computations (FEM, FDM, FEBM, FDTD) lead to the analysis of a large set of algebraic equations. The properties of parallel implementation of FDTD algorithm and the conjugate gradient method (CGM) were presented.

DOI: 10.3233/JAE-2002-362

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 13, no. 1-4, pp. 393-398, 2002

Authors: Sobhi-Najafabadi, Bijan | Göl, Özdemir | Nafalski, Andrew

Article Type: Research Article

Abstract: Simple impedance models are routinely used in the design of permanent magnet generators. Unfortunately, this invariably results in poor prediction accuracy, particularly because saturation is not taken into account. This paper presents a method, which helps improve prediction accuracy by using field models as an adjunct to adjust the model parameters to the prevailing flux conditions in an adaptive mode.

DOI: 10.3233/JAE-2002-358

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 13, no. 1-4, pp. 399-404, 2002