Analytical preconditioners for Neumann elastodynamic boundary element methods

Recent works in the boundary element method (BEM) community have been devoted to derivation of fast techniques perform matrix-vector product needed iterative solver. Fast BEMs are now very mature. However, it has shown that number iterations can significantly hinder overall efficiency BEMs. The robust preconditioners is inevitable increase size problems be considered. Analytical offer a interesting strategy by improving spectral properties integral equations ahead discretization. main contribution this paper propose new analytical treat Neumann exterior scattering 2D and 3D elasticity. These local approximations adjoint Neumann-to-Dirichlet map. We three with different orders. resulting preconditioned Combined Field Integral Equations (CFIEs). An study confirms expected behavior preconditioners, i.e., better eigenvalue clustering especially elliptic part contrary standard CFIE first-kind. provide various numerical illustrations for smooth non geometries. In particular, independent density discretization points per wavelength which not case CFIE. addition, less sensitive frequency.