Abstract
Abstract
Based on the NACA0012 airfoil, different types of protrusions namely serrated protrusions and arc-shaped protrusions are set near the trailing edge. Both new airfoils have a certain decrease in flow performance however there is a significant reduction in aerodynamic noise of airfoils. This is because the protrusions damage the vortex near the trailing edge. In addition, the noise reduction of serrated protrusions is more significant than t of arc-shaped protrusions, about 2.7dB.