Surface elements for modelling 3D fields around thin iron sheets

A method that allows thin iron sheets to be included in 3-D finite element models of magnetostatic fields is introduced. This method avoids having to model the sheet using volume elements. This is advantageous, as very fine meshes are conventionally required to model sheets which are thin compared to the other dimensions if elements with a poor aspect ratio are to be avoided. The technique has been available in the MEGA package and has proved useful in modeling electromagnetic compatibility problems, in shielding for magnetic resonance imaging magnets, and for the effects of ships and dockyards on the Earth's magnetic field.<
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