Flux Distribution in a Linear Magnetic Shield

The two-dimensional flux distribution in a magnetic shield of constant permeability and conductivity is presented in a series of magnetic vector-potential contour plots. The plots show the leakage-flux tubes in the shield and in the shielded region. Three- dimensionless parameters representing the shielding 1) thickness, 2) skin depth, and 3) permeability are introduced as the flux-distribution variables. The induced eddy currents cause the resulting fields in the shield to be elliptically polarized and to break into a characteristic cell structure which increases in complexity with rising frequency.