Numerical Investigation of Flexibility Effects on the CFD-CSM Coupling of Deflected Delta Wing Control Surfaces

Numerical aeroelastic investigations are conducted for the Model53 delta wing with a deployed slat and two trailing-edge control surfaces at transonic speed and high dynamic pressure. The numerical method is based on coupled high-fidelity CFD-CSM simulations, which is implemented in the multi-disciplinary simulation environment SimServer. The DLR Tau Code is utilized to solve the Reynolds-Averaged Navier-Stokes (RANS) equations and a modal solver is employed to calculate the structural displacements. Control surface regions are modeled with a Chimera approach for hybrid grids. The main focus of the analysis is set on the appropriate handling of control surface deflections for coupled CFD-CSM simulations. Two cases are investigated: In the first case, the control surfaces are deflected for both, the aerodynamic and the structural grid. In the second case, only the control surfaces of the aerodynamic grid are deflected and the aerodynamic forces are transferred to the undeflected structural grid. Both cases are compared in terms of the resulting structural deformation and flow field. The differences between both approaches are minor.