Numerical simulation in aeroelasticity for complex configurations in a transonic flow

This paper presents numerical approaches for computing fluid/structure interactions in a transonic flow using Euler/Navier-Stokes solvers. The first method concerns the flutter simulation using the linearized Euler equations in the frequency domain. The second method concerns the direct fluid structure coupling in the time domain. The Euler/Navier-Stokes equations are solved on a multi-block structured mesh and are based on an ALE formulation. Specific tools are developed for the mesh deformations. A Finite Element Formulation is used to model the structural part of the aeroelastic problem. The use of a modal reduction for the structure and a dual timestep technique to simulate the unsteady aerodynamics reduces considerably the CPU times without detracting from the accuracy and the robustness of the simulations. These numerical methods are applied for static aeroelasticity and flutter prediction for complex civil and military configurations in transonic flow. The tools are tested for a Limit Cycle Oscillations (LCO) problem in 2D.