Treatment of unbounded skin-effect problems in the presence of material inhomogeneities

An iterative finite-element procedure is described for the solution of skin-effect problems, under the assumption of quasi-static TEM conditions. The systems considered consist of parallel straight conductors of arbitrary cross section, with inhomogeneous conductivity and permeability, embedded in an unbounded homogeneous dielectric medium. A fictitious boundary enclosing all the conductors is introduced; an initial guess for the magnetic vector potential is assumed on this boundary and is iteratively improved according to the Laplacian behaviour of the potential outside the conductors. An example of application to a simple transmission line is given