An Experimental Investigation on the Impact of Vortex Generators on the Aeroacoustics of a NACA 0012 Airfoil

This study experimentally investigates the aeroacoustic effects of vortex generators (VGs) on a stationary and pitching NACA 0012 airfoil at a Reynolds number of Re = 4.2 × 10^5. Two VG configurations are assessed. For the stationary airfoil, VGs induce only modest aerodynamic changes, slightly extending the linear lift range near stall without altering the abrupt stall onset. Near-field pressure fluctuations exhibit a minor redistribution of spectral energy, with reduced low-frequency content and a shift toward higher frequencies near stall, particularly toward the trailing edge. However, these changes do not result in a significant reduction in far-field noise, with only small decreases observed at post-stall angles of attack. For the pitching airfoil (kr = 0.02 and 0.1, a0 = 12◦, Aˆ = 4◦), VGs have minimal impact on phase-averaged far-field noise levels. Some differences are observed following the peak noise levels, suggesting a potential influence on flow reattachment. Further investigation is required to clarify their effectiveness under dynamic stall conditions.