A linearized method for the frequency analysis of three-dimensional fluid/structure interaction problems in all flow regimes

We present a computational fluid dynamics (CFD)-based linearized method for the frequency analysis of three-dimensional fluid/ structure interaction p roblems. This method is valid in the subsonic, transonic. and supersonic Ro w regimes. and is insensitive to the frequency or damping level of the soug ht-after coupled eigenmodes. It is based on the solution by an orthogonal i teration procedure of a complex eigenvalue problem derived from the lineari zation of a three-held fluid/structure/moving mesh formulation. The key com putational features of the proposed method include the reuse of existing un steady flow solvers. a second-order approximation of the flux Jacobian matr ix. and a parallel domain decomposition-based iterative solver for the solu tion of large-scale systems of discretized fluid/structure equations. While the frequency analysis method proposed here is primarily targeted at the e xtraction of the eigenpairs of a wet structure, we validate it with the flu tter analysis of the AGARD Wing 445.6, for which experimental data is avail able. (C) 2001 Elsevier Science B.V. All rights reserved.