On The Coupled NBEM And FEM For Some Electromagnetic Scattering Problems

In this thesis, we investigete the coupling of natural boundary element method (NBEM) and finite element method (FEM) for some electromagnetic scattering problems in the upper half of plane.Electromagnetic scattering problems in R2include transverse magnetic field and transverse electric field. For each case, the governing equation is first dis-cretized in time by the Newmark method, leading to a time-stepping scheme, where an exterior Helmholtz problem has to be solved in each time step. An artificial boundary (?)Ris introduced, a boundary condition on (?)R is obtained by the natural boundary reduction, and a variatinal problem of the coupled problem is given. The numerical methods of the variational problem is presented. Finally, some numerical examples are presented to illustrate the feasibility of the method.