Aerodynamic performance of a blunt trailing-edge airfoil affected by vortex generators and a trailing-edge wedge

Vortex generators and trailing-edge wedges are proposed to be adopted simultaneously to enhance aerodynamic performance of a blunt trailing-edge airfoil for wind turbines. To understand the impact and physics of these two devices on airfoil performance, investigation was carried out by numerical simulation on DU97-W-300 using CFD. Three-dimensional models, including baseline models, models fitted with vortex generators, models equipped with a trailing-edge wedge and models with both devices, were built and validated through the comparison between the simulation results and experimental data. The main aerodynamic parameters were obtained to evaluate the efficiency of these two accessories. Furthermore, pressure distributions with and without the two devices were presented, and the structures of induced vortices, as well as their interaction in downstream region were also analysed. The simulation shows that vortex generators and the trailing-edge wedge work well in concert. The combined effects of the two devices on airfoil performance are positive, especially in enhancement of lift and the restriction of drag. In addition, trailing-edge wedges are suitable for blunt trailing-edge airfoils due to their strength. And the wedge with a height under 1% chord yields a significant increase in maximum lift coefficient at the cost of an acceptable drag increment.