A Comparison of Different Approaches for Predicting Transonic Buffet Onset on Infinite Swept Wings

A comparative study is performed on three different approaches for prediction of transonic buffet onset infinite swept wings. All are based the unsteady Reynolds-averaged Navier–Stokes (URANS) equations, and include: quasi-3D fully-3D global stability analysis corresponding steady 2.5D RANS solutions direct numerical solution 3D URANS equations. The results presented an wing ONERA OAT15A airfoil section. shown to be accurate most efficient and, thus, best suited this spanwise-uniform flow. ensures same accuracy, provided that grid-step in spanwise direction sufficiently small. It much more demanding terms computer memory but can extended more-general configurations. Good agreement observed between critical conditions instability growth characteristics, providing a cross-validation methods assessment their computational demands.