Title :
Numerical analysis of eddy current problems, involving saddle-shaped coils in superconducting MRI magnets
Author :
Takahashi, Takao
Author_Institution :
Hitachi Ltd., Ibaraki, Japan
fDate :
9/1/1991 12:00:00 AM
Abstract :
The pulsed field of saddle-shaped x, y field gradient coils induces eddy currents in metallic structures within a superconducting magnetic resonance imaging (MRI) magnet. These eddy currents are three-dimensionally computed by a hybrid form of an finite-element method (FEM) and an integration method formulated on an electric vector potential. The eddy current effects are investigated while varying the resistivity and geometric parameters of cryogenic radiation shields. Applications of this calculation method for slit shields and actively shielded gradient coils, are presented.
Keywords :
biomedical NMR; eddy currents; finite element analysis; integration; magnetic shielding; superconducting magnets; FEM; actively shielded gradient coils; cryogenic radiation shields; eddy current problems; electric vector potential; field gradient coils; finite-element method; geometric parameters; integration method; magnetic resonance imaging; metallic structures; numerical analysis; resistivity; saddle-shaped coils; slit shields; superconducting MRI magnets; Conductivity; Eddy currents; Electric potential; Magnetic analysis; Magnetic fields; Magnetic resonance imaging; Magnetic shielding; Numerical analysis; Superconducting coils; Superconducting magnets;
Journal_Title :
Magnetics, IEEE Transactions on
