Title :
Magnetometric Demagnetizing Factors for Various Shapes of Rotational Symmetry
Author :
Soda, Naoya ; Horii, Tatsuo ; Kobayashi, Masanori
Author_Institution :
Dept. of Electr. & Electron. Eng., Ibaraki Univ., Hitachi, Japan
Abstract :
We have investigated the magnetometric demagnetizing factors of rotation-symmetrical magnetic bodies of relative permeability mu placed in a uniform magnetic field parallel to the axis of rotation. The bodies we considered include a cylinder, a sphere, a bicone, and a rotating astroid. We numerically calculated the magnetometric demagnetizing factors from the surface magnetic charge densities sigma obtained by the surface magnetic charge simulation method. We show that the magnetometric demagnetizing factors for various shapes of rotation-symmetrical bodies are significantly different from those of a sphere. We have determined the shape producing the largest demagnetizing field in ferromagnetic bodies with sufficiently large relative permeability mu . We report the magnetometric demagnetizing factors for uniformly magnetized bodies (mu = 1 , i.e., susceptibility chi = 0 ) of various shapes.
Keywords :
demagnetisation; ferromagnetism; magnetic permeability; magnetic susceptibility; surface magnetism; bicone; cylinder; ferromagnetic bodies; magnetometric demagnetizing factors; relative permeability; rotating astroid; rotation-symmetrical magnetic bodies; rotational symmetry; sphere; surface magnetic charge densities; surface magnetic charge simulation method; susceptibility; uniform magnetic field; Demagnetization; Engine cylinders; Magnetic fields; Magnetic flux; Magnetic materials; Magnetic susceptibility; Magnetization; Magnetostatics; Permeability; Shape; Bicone; constant permeability; cylinder; demagnetizing factor; magnetostatics; rotating astroid; rotational symmetry;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2009.2023117