Natural snowstorms can be used to improve our understanding of how wind turbines interact with the atmosphere, according to a study in Nature Communications this week. The findings may allow for future improvements in turbine design and wind farm power production.
Models of turbulent flow around wind turbines are normally simulated in laboratory wind tunnels, seeded with small particles, using equipment on a metre-scale. However, flow characteristics can vary with scale and wind turbines are often as tall as city office blocks with blades of a similar span.
Jiarong Hong and colleagues have developed a more realistic way to gain measurements on a much larger scale by using their natural laboratory with snow falling in the wake of a full-scale wind turbine 80m high with blades 48m long. Measurements were taken at night and a light sheet illuminated the heavily-falling snowflakes so that pictures and videos could be recorded of the vortices that developed due to the rotating blades. Image analysis enabled accurate measurements of the turbulence generated by this utility-scale wind turbine.
The turbulent structures in the wake of a turbine can potentially impact both the power production capability of the turbines and the mechanical strain or load on the framework. The research could inform the siting of new wind farms and improve the efficiency and reliability of the turbines.