ABSTRACT
Trailing edge serrations have shown remarkable ability to reduce noise, but their effectiveness can be significantly impacted by flow misalignment, particularly under aerodynamic loading conditions. This paper presents a comprehensive study on the effect of incorporating streamwise vane treatments at the root of the trailing edge serrations on its noise reduction performance. Experiments were performed on a 100 mm chord NACA 0012 wing model with sawtooth type trailing edge serration. The aeroacoustic performance was investigated for serrations with non-zero flap angle at various angles of attack between -5° and 8.5°. The findings reveal that streamwise vanes can reduce the high-frequency noise by over 5 dB when placed at the root. Furthermore, particle image velocimetry measurements in the wall-normal plane demonstrate a significant decrease in cross-flow and turbulence generation when the treatment was placed near the root of serrations. In addition, the load measurements indicate no noticeable variation in the lift coefficient and up to 6% increase in the drag coefficients in the pre-stall region.
