High-order local arti®cial boundary conditions for problems in unbounded domains
نویسندگان
چکیده
In this paper we present error estimates for the ®nite element approximation of Poisson and modi®ed Helmholtz equations outside an obstacle or in a semi-in®nite strip in the plane. The ®nite element approximation is formulated on a bounded domain using a local approximate arti®cial boundary condition. In fact there is a sequence of local approximate boundary conditions for a given arti®cial boundary. Our error estimates are based on the mesh size and the location of the arti®cial boundary. The numerical stability and robustness of the method are discussed. Numerical experiments are presented to demonstrate the performance of the method and our error estimates. Ó 2000 Elsevier Science S.A. All rights reserved.
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