Abstract
From the molecular current viewpoint, an analytic expression exactly describing magnetic field distribution of rectangular permanent magnets magnetized sufficiently in one direction was derived from the Biot-Savart’s law. This expression is useful not only for the case of one rectangular permanent magnet bulk, but also for that of several rectangular permanent magnet bulks. By using this expression, the relations between magnetic field distribution and the size of rectangular permanent magnets as well as the magnitude of magnetic field and the distance from the point in the space to the top (or bottom) surface of rectangular permanent magnets were discussed in detail. All the calculating results are consistent with experimental ones. For transverse magnetic field which is a main magnetic field of rectangular permanent magnets, in order to describe its distribution, two quantities, one is the uniformity in magnitude and the other is the uniformity in distribution of magnetic field, were defined. Furthermore, the relations between them and the geometric size of the magnet as well as the distance from the surface of permanent magnets were investigated by these formulas. The numerical results show that the geometric size and the distance have a visible influence on the uniformity in magnitude and the uniformity in distribution of the magnetic field.
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References
Moon F C.Superconducting Levitation[M]. New York: John Wiley & Sons, Inc, 1994.
WANG, Jia-su, WANG Su-yu.Application of Superconducting Technology[M]. Chengdu: Chendu University Science and Techology Press, 1995. (in Chinese)
ZHANG Yong, XU Shan-gang. HighT c Superconducting mag-lev model vehicles[J].cryogenics and Superconductivity, 199826(4):35–39. (in Chinese)
Enokizono M, Matsumura K, Mohri F. Magnetic field of anisotropic permanent magnet problems by finite element method[J].IEEE Transaction on Magnetics, 199733(2):1612–1615.
Harrold W J. Calculation of equipotentials and flux lines in axially symmetrical permanent magnet assemblies by computer[J].IEEE Transaction on Magnetics, 19728(1):23–29.
SUN Yu-shi. On the calculating models of permanent magnets[J].Acta Electronica Sinica, 1982, (5):86–89. (in Chinese)
LI Jing-tian, ZHENG Qin-hong, SONG Yi-de,et al., Computation of permanent magnet field with boundary element method[J].New Technology Electrician and Electric Energy, 19981:7–9. (in Chinese)
Campbell P, Chari M V K, Angeio J D. Three-dimension finite element solution of permanent magnet machines[J].IEEE Transaction on Magnetics, 198117(6):2997–2999.
LIN De-hua, CAI Cong-zhong, DONG Wan-chun. A study of the distribution of magnetic induction over the surface of square permanent magnet[J].Engineering Course Physics, 19999(2):5–9. (in Chinese)
CHEN In-gann, LIU Jian-xiong, Weintein Roy,et al. Characterization of YBa2Cu3O7, including critical current density, by trapped magnetic field[J].Journal Appllied Physics, 199272 (3):1013–1020.
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Communicated by Chen Shan-lin
Foundation items: the National Natural Science Foundation of China (10132010); the National Natural Science Foundation of China for Outstanding Young Researchers (10025208); Pre-Research for Key Basic Researches of the Ministry of Science and Technology of China; the Fund of Excellent Teachers in University of the Education Ministry of China
Biographies: Gou Xiao-fan (1971 ∼), Doctor, Zheng Xiao-jing (Corresponding-author)
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Xiao-fan, G., Yong, Y. & Xiao-jing, Z. Analytic expression of magnetic field distribution of rectangular permanent magnets. Appl Math Mech 25, 297–306 (2004). https://doi.org/10.1007/BF02437333
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DOI: https://doi.org/10.1007/BF02437333