Numerical investigation on windturbine power enhancement using windbreaks

Traditionally, windbreaks have been widely used in the agricultural sector to provide shelter for plants and livestock from the high-speed wind. In the lee of windbreaks, the wind speed is effectively reduced. Recently, Tobin et al. discovered that windbreaks can be used to increase the power production of wind turbines. As the wind passes through the windbreak, it will be deflected causing an upward change in direction and the flow speed-up effect will be generated. Then, the wind turbine can extract extra energy from the deflected wind. In the present study, the effects of the inclined angle of the windbreak on the power output of a single wind turbine are investigated using computational fluid dynamics (CFD). The Reynolds-averaged Navier-Stokes equations (RANS) with the k-ω SST turbulence model are utilized. The results suggest that windbreak can increase the streamwise velocity at the rotor plane. The increased streamwise velocity at hub-height results in approximately 13.25% increase in power production. There is also an increase in turbulence intensity and wind velocity along the vertical axis. Moreover, the inclination of the windbreak is inversely proportional to the streamwise velocity and turbulence intensity. Also, the power output of the wind turbine tends to reduce as the inclination of the windbreak increases. The most powerful production of the wind turbine is obtained using the windbreak without any inclination. However, the increase in turbulence intensity might affect the wind turbine’s lifetime due to fatigue loading. Further evaluation of trade-offs between power enhancement and lifetime reduction of the wind turbine with windbreaks is needed.