Shifted-Laplacian Preconditioners for Heterogeneous Helmholtz Problems
نویسنده
چکیده
We present an iterative solution method for the discrete high wavenumber Helmholtz equation. The basic idea of the solution method, already presented in [18], is to develop a preconditioner which is based on a Helmholtz operator with a complex-valued shift, for a Krylov subspace iterative method. The preconditioner, which can be seen as a strongly damped wave equation in Fourier space, can be approximately inverted by a multigrid method.
منابع مشابه
Comparison of multigrid and incomplete LU shifted-Laplace preconditioners for the inhomogeneous Helmholtz equation∗
Within the framework of shifted-Laplace preconditioners [Erlangga, Vuik, Oosterlee, Appl. Numer. Math., 50(2004), pp.409–425] for the Helmholtz equation, different methods for the approximation of the inverse of a complex-valued Helmholtz operator are discussed. The performance of the preconditioner for Helmholtz problems at high wavenumbers in heterogeneous media is evaluated. Comparison with ...
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