Evaluation of a Physics-Based Unsteady RANS Method for Buffet Onset Prediction
Daniel Maldonado, Jeffrey A. Housman, Ercan Dumlupinar, Gerrit-Daniel Stich, Jared C. Duensing, William E. Milholen · 2024
A physics-based moving-body unsteady Reynolds Averaged Navier-Stokes based method for predicting the onset of transonic buffet is described. Four test cases of varying complexity are chosen to evaluate the approach; an ONERA OAT15A supercritical airfoil, a NACA0012 airfoil, the NASA High-Speed Common Research Model (CRM-HS), and the Boeing SUGAR Phase V Transonic Truss Braced Wing (TTBW). A wide range of configurations is covered from airfoils, to a conventional aircraft design, to a more novel concept like the TTBW. These cases demonstrate various buffet instability modes including the low frequency airfoil buffet mode, the moderate frequency swept buffet mode, and the higher frequency shear-layer mode. Detailed numerical studies developed guidelines relating to choice of low-dissipation schemes, proper time- step selection, and mesh resolution requirements.