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DOE OSTI · 2430220

Enabling "Fuel" Switching through On-Demand Wind Control

Brown, Kenneth·Cheung, Lawrence·Houck, Daniel Russell·deVelder, Nathaniel
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Abstract

This work demonstrates that classical shear-flow stability theory can be successfully applied to modify wind turbine wakes and also explains the success of several emerging, empirically-arrived control methods (i.e., dynamic induction and helix control). Linear stability theory predictions are extended to include the effects of non-axisymmetric inflow profiles, such as wind shear, which is shown to not strongly affect the primary forcing frequency. The predictions, as well as idealized large-eddy simulations using actuator-line representation of the turbine blades, agree that the n = 0 and ±1 modes have faster initial growth rates than higher-order modes, suggesting the lower-order modes are more appropriate for wake control. Exciting the lower-order modes with periodic pitching of the blades produces higher entrainment into the wake and consequently faster wake recovery.

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Brown, Kenneth, Cheung, Lawrence, Houck, Daniel Russell, deVelder, Nathaniel. 2024-08-17. Enabling "Fuel" Switching through On-Demand Wind Control. https://doi.org/10.2172/2430220

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