Published online by Cambridge University Press: 16 January 2007
This paper proposes and analyzes a BEM-FEM scheme to approximatea time-harmonic diffusion problem in the plane with non-constantcoefficients in a bounded area. The model is set as a Helmholtztransmission problem with adsorption and with non-constantcoefficients in a bounded domain. We reformulate the problem as afour-field system. For the temperature and the heat flux we usepiecewise constant functions and lowest order Raviart-Thomaselements associated to a triangulation approximating the boundeddomain. For the boundary unknowns we take spaces of periodicsplines. We show how to transmit information from the approximateboundary to the exact one in an efficient way and provewell-posedness of the Galerkin method. Error estimates areprovided and experimentally corroborated at the end of the work.