轴向均匀磁化圆柱形磁介质的退磁场和退磁因子

The demagnetizing field and factor of uniformly magnetized cylinder

退磁因子是描述磁介质磁化特性的重要参量.本文采用磁荷观点,推导出了轴向均匀磁化圆柱体内任意一点的退磁场和退磁因子表达式;分析了圆柱体形状等因素对退磁因子的影响;通过数值计算,研究了圆柱体轴线上轴向退磁因子与圆柱体形状的关系.结果表明:圆柱体轴线上各点的横向退磁因子等于零;圆柱体轴线中部的轴向退磁因子较小,两端附近的轴向退磁因子较大;随着圆柱体长度的增大,圆柱体内各点的轴向退磁因子整体减小.

Demagnetizing factor is an important physical quantity for describing the magnetizing characteristics of magnetic medium. In this paper, based on the theory of magnetic charge, the expressions of demagnetizing field and demagnetizing factors of uniformly axial magnetized cylinder medium were obtained. The influence of cylinder shape on demagnetizing factor was analyzed. By numerical computing, the relation between the axial demagnetizing factors of points at axis and cylinder shape was fully discussed. The conclusions are： （1） The transverse demagnetizing factors of points at axis are zero; （2） The axial demagnetizing factors of points at central part of axis are smaller,and those points near ends of axis are bigger （3） As the cylinder becomes longer, the demagnetizing factors decrease.