The discrete arti®cial boundary condition on a polygonal arti®cial boundary for the exterior problem of Poisson equation by using the direct method of lines
نویسندگان
چکیده
The numerical simulation for the exterior problem of Poisson equation is considered. We introduced a polygonal arti®cial boundary Ce and designed a discrete arti®cial boundary condition on it by using the direct method of lines. Then the original problem is reduced to a boundary value problem de®ned in a bounded computational domain with a polygonal boundary. The ®nite element approximation of this reduced boundary value problem is considered and it is proved that the ®nite element approximate problem is well posed. Furthermore numerical examples show that the discrete arti®cial boundary condition is very eective and more accurate than the Neumann boundary condition which is often used in engineering literatures. Ó 1999 Elsevier Science S.A. All rights reserved.
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