Collaborative Research: CBET-EPSRC: Unwinding entrainment processes in wind farm to wind farm interactions

Electricity production from wind energy is increasing rapidly in the U.S. and U.K. When more wind plants are added in areas of high wind resource availability, the distance between neighboring plants becomes shorter. The wake from a wind plant can extend miles downstream of the plant, which means that it may affect the efficiency of a downstream plant within the wake. Most research regarding wakes from wind turbines has focused on the effects from a single turbine. Results from this research has been used to optimize the design and performance of a wind plant. However, interactions between neighboring plants have not been studied extensively. This project will use a combination of experiments and numerical analysis to develop relationships between wind farms under conditions when one wind plant affects downstream ones. The models will be implemented to current wind farm engineering flow-tools, which will increase their accuracy and efficiency, and contribute to more accurate planning of wind farms. The proposed research will investigate the issue of successive wind farm wake interactions and develop reduced-order model representations for use by industry and national laboratories. Specifically, the research will quantify and develop models for (i) the production and recovery of momentum deficit that a single wind farm generates at its downstream outflow, and (ii) this outflow interaction with downstream farms. Detailed large- and small-scale laboratory experiments and high-fidelity numerical simulations will be used to consider a multitude of real-world conditions, including changes in ground surface roughness, the Coriolis force, thermal stratification, global blockage and entrainment between the atmospheric boundary layer (ABL) and the wind farm wakes. This collaborative U.S.-U.K. project is supported by the U.S. National Science Foundation (NSF) Division of Chemical, Bioengineering, Environmental and Transport Systems (CBET) and the Engineering and Physical Sciences Research Council (EPSRC) of United Kingdom Research and Innovation, where NSF funds the U.S. investigator and EPSRC funds the partners in the United Kingdom. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.