| Description |
Wind energy is one of the most rapidly growing sources of energy in the United States. With higher energy demands, next generation wind turbines will have larger blades and taller towers to increase the harvested power. However, in order to design taller towers, it is important to have a good understanding of how the wind flow interacts with turbines during operation. The aim of this research is to compute the loads on wind turbines for increasing heights under different atmospheric stratifications (convective, neutral, and stable) and within different turbine configurations (lone-standing wind turbine and turbine within a very large wind farm). To develop this study, an in-house numerical code has been used, capable of reproducing a realistic atmospheric flow as well as wind turbines. To compute the detailed turbine’s rotor and tower loads, an additional open-source software developed by the National Renewable Energy Laboratory (NREL), so-called FAST, has been used. Streamwise wind turbine loads are computed, and the influence of different wind characteristics on the turbine’s loads have been considered. We identify that wind velocity, turbulence, and wind shear play an important role on the wind turbine loads; the frequencies of the incoming wind velocity and rotation of the blades both affect the frequencies of the wind turbine loads. Results also show that the rotor thrust is the most dominant force acting on the wind turbine during the operational phase and has the strongest influence on the shear and bending moments of the wind turbine tower. From this study, it is also found that by increasing the turbine tower height, power output can be increased by capturing energy from the low-level jet in the single wind turbine case, while for the wind farm case, improvements are minimal. |
