‘Breezy Mysteries’ – Understanding Wind Turbine Wakes Using High-Fidelity Simulation & Visualization
Department of Aerospace Engineering, Penn State University
Wind Energy continues its growing impact on the global electricity market as a viable source of renewable energy. This seminar demonstrates how a combination of high-fidelity simulation and visualization can be used towards a deeper understanding of the flow physics inherent to wind turbine wakes. The Actuator Line Method (ALM) within the OpenFOAM framework is used as a turbine model in a Large Eddy Simulation (LES) of the atmospheric boundary layer (ABL). The ‘Breezy Mysteries’ include subtle processes in the effect of the ABL stability state on the recovery process of the wake momentum deficit downstream of wind turbines, power distribution in an array of wind turbines, and breakdown of tip vortices. Differences between ALM modeling approaches are addressed. Additional quantitative analyses include distributions of Reynolds stresses and turbulent kinetic energy (TKE) along vertical and horizontal lines. Complete flux integrals along wake planes reveal some new insight into the recovery process as a result of different behavior above/below turbine hub height. In addition, state-of-the-art flow visualization of high-resolution LES data shows sudden vortex breakdown due to coincident ABL low-speed streaks and updrafts in an unstable atmosphere. The seminar concludes with a summary of future research needs and opportunities.
Date(s) - 03/02/2017
4:00 pm - 5:00 pm
1062 Bainer Classroom