Numerical investigation of active control for an S809 wind turbine airfoil

Abstract

Recently, the necessity of using natural resources, like wind energy, has been greatly highlighted due to the limitation of fossil energy and the increase of environmental pollution. Therefore, many countries have begun their investigation in wind power generators. Also, National Institutes such as Riso (Denmark), ECN (Netherlands), and NREL (USA) have conducted many studies in this area. With the development of new design techniques, the size of wind turbines has been gradually increasing. So, the performance of wind turbines has become even more important. The flow control device is used for higher aerodynamic performance. In the present study, the aerodynamic performance of a wind turbine blade equipped with a flow control device is studied using a commercial flow analysis code, Ansys Fluent. The model used for calculation is an S809 airfoil that was tested in the low-turbulence wind tunnel of TU Delft. First, steady state results for the S809 airfoil, with change of angle of attack, are compared with experimental results. These steady state results show good agreement with the experimental results. Second, the computational results for the flow control device are presented for the aerodynamic performance of the S809 airfoil. When the position of the jet slot is x/c=0.6, computed results show a maximum lift coefficient of α = 14.24°. When the position of the jet slot is x/c = 0.025, computed results show a stall delay of α = 14.24° and 20.15°.