Finite element approximation of spectral acoustic problems on curved domains

Summary. This paper deals with the finite element approximation of the displacement formulation of the spectral acoustic problem on a curved non convex two-dimensional domain. Convergence and error estimates are proved for Raviart-Thomas elements on a discrete polygonal domain h 6 in the framework of the abstract spectral approximation theory. Similar results have been previously proved only for polygonal domains. Numerical tests confirming the theoretical results are reported. Mathematics Subject Classification (1991): 65N25, 65N30, 70J30 Key words Acoustic vibrations, finite element spectral approximation, curved domains.