Automatic treatment of multiply connected regions in Integral Formulations

This paper deals with the volume integral formulation of the eddy current problem in terms of the electric vector potential. Its aim is to present a simple topological algorithm for finding the additional degrees of freedom required in the discretization of a multiply connected region when using edge elements. The algorithm is completely automatic and it is based, as other previous approaches, on the application of the spanning tree technique on the graph made by the edges and nodes of the finite element mesh lying on the boundary surface of the conducting domain.