3-D Electromagnetic Scattering Computation in Free-Space With the FETI-FDP2 Method

Ivan Voznyuk, Herve Tortel, Amelie Litman
2015 IEEE Transactions on Antennas and Propagation  
The electromagnetic dual-primal finite element tearing and interconnecting (FETI-DPEM) method is a nonoverlapping domain decomposition method developed for the finite element analysis of large-scale electromagnetic problems, where the corner edges are globally numbered. This paper presents an extension of the FETI-DPEM2 method, named FETI-Full Dual Primal (FETI-FDP2), where more flexible Robin-type boundary conditions are imposed, on the inner interfaces between subdomains as well as on the
more » ... well as on the corner edges, leading to a new interface problem. Its capacities are tested in the framework of a 3D free-space scattering problem, with a scattered field formulation and a computational domain truncated by Perfectly-Mathed Layers (PML). First we compare its accuracy with respect to other FETI-DPEM2 methods and to a complete resolution of the FEM problem thanks to a direct sparse solver. We show that the convergence of iterative solvers are affected by the presence of the PML and can be accelerated by means of a more accurate approximation, between adjacent subdomains, of the Dirichlet-to-Neumann (DtN) operator. The effectiveness of the iterative solvers are also considered for different test cases. The advantages of the proposed FETI-FDP2 method combined with the associated DtN approximation is numerically demonstrated, regardless the chosen working frequency or the iterative solvers. Index Terms-Finite Element Method (FEM), Domain decomposition method, FETI-DPEM method, non-conformal mesh, arbitrary partitioning, Krylov subspace iterative method, electromagnetic propagation and scattering, three-dimensional configuration, Perfectly Matched Layer (PML) PLACE PHOTO HERE Ivan Voznyuk was born in Russia in 1988. He received the M.S. degree in Applied Mathematics from the Novosibirsk State Technical University, Russian Federation and the Ph.D. in Physics from the University of Aix-Marseille, France in 2014. During his thesis, which was carried out at Institut Fresnel, he worked on the development of advanced electromagnetic numerical schemes for forward and inverse scattering applications. He is currently a postdoctoral researcher at CEA-LETI, Grenoble, France where his current research interests include the conception and the optimisation of various types of meta-materials.
doi:10.1109/tap.2015.2417977 fatcat:mmh6c2tjrvcfdohjgyv6ntrqvq