Active Flow Control of a Symmetric Airfoil Using Steady Jet Injection: A Numerical Study

This study numerically investigates the effects of steady blowing on a NACA 0015 airfoil to control flow separation and enhance aerodynamic performance across a range of angles of attack. CFD simulations were performed at Re = 6×105 using the standard k − ε turbulence model, showing good agreement with previous experimental and numerical studies. The influence of injection location was assessed at x/c = 0.00 and x/c = 0.17. Leading-edge injection (x/c = 0.00) was found most effective in increasing lift and delaying separation at moderate AoA (3°–11°), yielding the highest lift-to-drag ratios. Injection at x/c = 0.17 slightly reduces drag at zero incidence. At higher AoA (≥12°), both injection positions increase drag and reduce CL /CD, indicating that excessive injection can intensify separation. The results demonstrate that properly positioned injection can significantly improve aerodynamic efficiency, with leading-edge injection being optimal for practical operation.