矩形永磁体磁场分布的解析表达式  

Analytic Expression of Magnetic Field Distribution of Rectangular Permanent Magnets

作　　者：苟晓凡[1] 杨勇[1] 郑晓静[1] 

机构地区：[1]兰州大学物理科学与技术学院力学系,兰州730000

出　　处：《应用数学和力学》2004年第3期271-278,共8页Applied Mathematics and Mechanics

基　　金：国家自然科学基金重点项目(10132010);国家杰出青年科学基金资助项目(10025208);科技部重点基础研究预研项目;教育部优秀教师基金资助项目

摘　　要：　从分子环流模型出发,利用毕奥＿萨伐尔定理,对于仅在一个方向均匀完全充磁的矩形永磁块体,导出了其外部空间磁场分布的解析表达式·　该解析式能精确描述一块至多块按极性相反并列放置时矩形永磁体外部空间的磁场分布·　针对单块永磁体,还分析了磁场分布与永磁体几何尺寸之间的依赖关系,以及磁场大小随外部空间点离开永磁体表面距离之间的关系;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.

关 键 词：永磁体 磁场分布 解析公式 

分 类 号：O441.6[理学—电磁学]