Delayed Detached Eddy Simulation of a Stall Flow Over NACA0012 Airfoil Using High Order Schemes

Abstract

Delayed-Detached Eddy Simulation (DDES) is conducted to simulate aerodynamic stall flow over NACA0012 airfoil at 45 ◦ angle of attack. DDES is an improved version of DES97 to avoid Modeled-Stress Depletion (MSD) in attached boundary layer by redefining the length scale of DES97. The test of DDES for the flat plate shows that the delayed LES function facilitates DDES to preserve eddy viscosity even with a severe grid that makes DES to undergo MSD. For comparison, DES97 and URANS also were conducted for the stalled NACA 0012 airfoil flow. DDES and DES predicted the drag coefficient accurately, while URANS overpredicted the drag by 33.6%. Both DES and DDES appear to be satisfactory to simulate the stalled airfoil flow at high angle of attack, in which the large structure of vortex are dominant.