Aerodynamic performance analysis of a trailing-edge flap for wind turbines

Abstract

In this paper, a trailing-edge flap is designed based on the wind turbine airfoil S809. The aerodynamic performance and flowfield of the proposed trailing-edge flap airfoil are predicted by computational fluid dynamics (CFD) at angles of attack from -5° to 12.5°. The lift coefficient, drag coefficient, pressure contour, and streamline distribution of the proposed trailing-edge flap airfoil are analyzed and then compared with those of the traditional flaps. The results illustrate that the lift coefficient and the lift-to-drag ratio of the trailing-edge flap are markedly larger than those of the traditional flaps and that the trailing-edge flap can effectively improve the stall characteristics of the trailing-edge airfoil.