1 research outputs found
Influence of Yaw Misalignment on Wind Turbine Wakes and Power Production Under Different Atmospheric Conditions: An LES and Analytical Modeling Study
No full textAs global reliance on renewable energy grows, optimizing wind farm performance has become essential for meeting sustainable energy demands. The interaction between wind turbines and the atmospheric boundary layer presents significant challenges, particularly in understanding wake dynamics and power production under varying atmospheric conditions and yaw misalignment. This thesis investigates the use of WRF-SADLES and an analytical wake model developed by Bastankhah and Porté-Agel (2016) to evaluate yaw misalignment as a wake mitigation strategy.
Simulations are conducted for two distinct atmospheric conditions with varying yaw angles to identify best practices for optimizing power production relative to non-yawed configurations. A two-turbine system, where the upwind turbine is yawed, is analyzed to capture the complex interactions between upwind and downwind turbines. Power production is evaluated across different turbine spacings, yaw angles, and atmospheric conditions, capturing a broad spectrum of scenarios. Key wake phenomena, such as wake deflection, wake recovery, and wake curling, are analyzed for their contributions to total power production.
The LES data generated with WRF-SADLES is used to calibrate and validate an analytical wake model. The analytical model demonstrated reasonable agreement with LES results for non-yawed and moderate yaw angles, successfully capturing the primary mechanisms driving power production under yaw misalignment. However, at larger yaw angles, it struggled to represent the asymmetric wake shapes associated with wake curling. These findings highlight the highly interdependent nature of yaw misalignments effectiveness, which is primarily governed by the extent to which wake deflection and recovery improve inflow conditions for the downwind turbine. While not universally beneficial, yaw misalignment can be a viable strategy when these improvements sufficiently compensate for the yaw-induced power loss of the upwind turbine.
Results further emphasize that the nuanced effectiveness of yaw misalignment depends on a delicate balance of atmospheric stability, turbine spacing, yaw angles, and site-specific conditions. Moderate yaw angles (10 −20 degrees) offer reliable performance, while more aggressive yawing benefits configurations with limited turbine spacing ( 10 x/D). The convective atmosphere enhanced power gains, reinforcing yaw misalignment as a promising wake mitigation strategy when tailored to favorable wind farm configurations. This research contributes to the growing body of evidence supporting yaw misalignment’s potential while underscoring the need for further advancements in LES and analytical modeling to refine its application across diverse operating environments.Masteroppgave i energiENERGI399MAMN-ENER
