GOU Xiao-fan, YANG Yong, ZHENG Xiao-jing. Analytic Expression of Magnetic Field Distribution of Rectangular Permanent Magnets[J]. Applied Mathematics and Mechanics, 2004, 25(3): 271-278.
 Citation: GOU Xiao-fan, YANG Yong, ZHENG Xiao-jing. Analytic Expression of Magnetic Field Distribution of Rectangular Permanent Magnets[J]. Applied Mathematics and Mechanics, 2004, 25(3): 271-278.

# Analytic Expression of Magnetic Field Distribution of Rectangular Permanent Magnets

• Rev Recd Date: 2003-10-31
• Publish Date: 2004-03-15
• 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.
•  [1] Moon F C.Superconducting Levitation[M].New York:John Wiley & Sons, Inc,1994. [2] 王家素,王素玉.超导技术应用[M]. 成都: 成都科技大学出版社,1995. [3] 张永,徐善纲. 高温超导磁悬浮模型车[J].低温与超导,1998,26(4):35—39. [4] Enokizono M,Matsumura K， Mohri F. Magnetic field of anisotropic permanent magnet problems by finite element method[J].IEEE Transaction on Magnetics,1997,33(2):1612—1615. [5] Harrold W J. Calculation of equipotentials and flux lines in axially symmetrical permanent magnet assemblies by computer[J].IEEE Transaction on Magnetics,1972,8(1):23—29. [6] 孙雨施.关于永磁的计算模型[J]. 电子学报,1982,(5):86—89. [7] 李景天,郑勤红,宋一得,等.用边界元法计算永磁体磁场[J]. 电工电能新技术,1998,(1):7—9. [8] Campbell P,Chari M V K,Angeio J D. Three-dimension finite element solution of permanent magnet machines[J].IEEE Transaction on Magnetics,1981,17(6):2997—2999. [9] 林德华,蔡从中,董万春. 方型永磁体表面磁感应强度分布的研究[J].工科物理,1999,9(2):5—9. [10] CHEN In-gann,LIU Jian-xiong,Weintein Roy,et al.Characterization of YBa2Cu3O7,including critical current density,by trapped magnetic field[J].Journal Appllied Physics,1992,72(3):1013—1020. doi: 10.1063/1.351826

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