The quality of aeroelastic predictions strongly depends on the quality of aerodynamic predictions. At the boundary of a typical flight envelope, special flow conditions may arise, which challenge the conventional Reynolds-averaged Navier–Stokes (RANS) approach beyond reasonable limits.
Test Case 3 of the Second AIAA Aeroelastic Prediction Workshop is a representative test case, where the flow over a supercritical wing separates downstream of the shock waves and generates large turbulent lengthscales.
In this study, RANS predictions are compared to those obtained in this particular test case with the more sophisticated hybrid RANS–large eddy simulation (LES) approach, in particular with the Spalart–Allmaras–delayed detached eddy simulation model. Results are indeed closer to experimental data.
However, the costs associated with this approach are much higher. It is argued that adopting hybrid RANS–LES modelling is not a simple model switch.
