Numerical analysis of eddy current problems, involving saddle-shaped coils in superconducting MRI magnets

Author

Takahashi, Takao

Author_Institution

Hitachi Ltd., Ibaraki, Japan

Volume

27

Issue

5

fYear

1991

fDate

9/1/1991 12:00:00 AM

Firstpage

3996

Lastpage

3999

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;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.104977

Filename

104977