Iterative solution of large-scale acoustic scattering problems with multiple right hand-sides by a domain decomposition method with Lagrange multipliers

An extension of the FETI-H method is designed for the solution of acoustic scattering problems with multiple right-hand sides. A new local pre-conditioning of this domain decomposition method is also presented. The potential of the resulting iterative solver is demonstrated by numerical experiments for two-dimensional problems with high wavenumbers, as many as 2:5million complex degrees of freedom, and a sweep on the angle of the incident wave. Preliminary results for a three-dimensional submarine problem are also included. The FETI-H method, whose numerical scalability with respect to the mesh and subdomain sizes was previously established, is shown here to be also numerically scalable with respect to the wavenumber