DOI: 10.1615/TSFP5
DIRECT NUMERICAL SIMULATION OF A LAMINAR SEPARATION BUBBLE ON A NACA-0012 AIRFOIL
Краткое описание
Direct numerical simulations (DNS) of a laminar separation bubble on a NACA-0012 airfoil at Rec = 5 × 104 and incidence 5° are presented. Initially volume forcing is introduced in order to promote transition. After obtaining sufficient data from this forced case, the explicitly added disturbances are removed and the simulation run further. Upon removal of disturbances, the turbulence is observed to 'self-sustain', and does not decrease in intensity. The forced and unforced cases are then compared, in order to investigate the dependency of bubble behaviour on the addition of disturbances. The results imply that forcing may potentially be used as a control measure to improve aerodynamic performance. Finally, a simplified DNS is presented that illustrates a mechanism for the self-sustaining turbulence that is observed, with implications for separation bubble modelling.