On the Finite Element Tearing and Interconnecting Method for Scattering by Large 3D Inhomogeneous Targets

The finite element tearing and interconnecting method (FETI) is applied to compute scattering by large 3D inhomogeneous targets. Two algorithms of FETI have been implemented for 3D scattering. The performance of these two FETI algorithms has been investigated in detail, particularly for large inhomogeneous targets. Numerical experiments show that the performance of FETI relies on the style of domain decomposition and inhomogeneity, which has not been carefully studied before. A trick for improving convergence of FETI is presented for inhomogeneous targets