Fluid-Structure Interaction for Flutter Predictions in Transonic and Supersonic Flows

This paper describes a numerical methodology coupling Euler/Navier-Stokes equations and structural modal equations for predicting flutter in transonic and supersonic flows. This coupling between Computational Fluid Dynamics (CFD) and Computational Structural Dynamics (CSD) is achieved through a Multi-Disciplinary Computing Environment (MDICE), which allows several computer codes or ‘modules’ to communicate in a highly efficient fashion. The present approach offers the advantage of utilizing well-established single-disciplinary codes in a multi-disciplinary framework. The flow solver is density-based for modeling compressible, turbulent flow problems using structured and/or unstructured grids. A modal approach is employed for the structural response. Two benchmark cases are employed to validate the present method. Flutter predictions in subsonic flows for an AGARD 445.6 wing at different Mach numbers (0.499 to 1.141) are presented and compared with experimental data. Supersonic plate flutter with Mach number range between 1.8 and 3.2 is studied and the critical Mach number is computed, our results are in a good agreement with the analytical solutions.