CFD-based aeroelastic eigensolver for the subsonic, transonic, and supersonic regimes

We describe a linearized computational fluid dynamics (CFD) method for comp uting an arbitrary number of eigensolutions of a given aeroelastic problem. The proposed method is based on the reengineering of a three-way coupled f ormulation previously developed for the solution in the time domain of nonl inear transient aeroelastic problems. It is applicable in the subsonic, tra nsonic, and supersonic flow regimes, and independently from the frequency o r damping level of the target aeroelastic modes. It is based on the computa tion of the complex eigensolution of a carefully linearized fluid-structure interaction problem, relies on the inverse orthogonal iteration algorithm, and reutilizes existing unsteady flow solvers. This is a validated method with the flutter analysis of the AGARD Wing 445.6 for which experimental da ta are available.