A METHOD TO COMPUTE THE SHIELDING OF A 3-D CONDUCTOR ARRAY BY A SEMIINFINITE PERMEABLE LAYER

A simple image method is described to predict the attenuation caused b y a semi-infinite permeable layer on the static magnetic field produce d by a 3-D conductor array. It is shown that the permeable layer gives rise to a array of current element images, of progressively smaller m agnitude and increasing distance from the layer. The convergence of th e method is examined. The method is applied to the problem of evaluati ng bottom electrode bus designs for a DC electric are furnace.